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Filed pursuant to Rule 424(b)(3)
Registration No. 333-114107

PROSPECTUS

$1,200,000,000

GRAPHIC


Floating Rate Convertible Senior Debentures Due 2023


        We issued, on October 1, 2003, the Floating Rate Convertible Senior Debentures due 2023 in a private placement. This prospectus will be used by the selling security holders to resell their debentures and the common stock issuable upon conversion of their debentures.

        We will pay interest on the debentures on March 15, June 15, September 15 and December 15 of each year, beginning December 15, 2003, at an annual rate equal to 3-month LIBOR, reset quarterly, minus 0.50%, except that we will pay interest for the initial interest period at an annual rate of 0.64% and we will never pay interest at a rate less than 0%.

        The holders may at any time prior to maturity convert the debentures into shares of our common stock at a conversion rate that will vary until September 15, 2008 depending on the applicable stock price. The minimum conversion rate is 24.2248 shares per $1,000 principal amount of debentures and the maximum conversion rate is 38.7597 shares per $1,000 principal amount of debentures. For more detail see "Description of Debentures—Conversion rights".

        On June 25, 2004, the last reported sale price for our common stock on the New York Stock Exchange was $24.55 per share. Our common stock is listed under the symbol "BMY".

        We may redeem for cash all or a portion of the debentures, at a price equal to 100% of the principal amount plus accrued and unpaid interest and liquidated damages, if any, to, but excluding, the date of redemption, at any time on or after September 21, 2008.

        Holders may require us to purchase for cash all or a portion of their debentures, at a price equal to 100% of the principal amount plus accrued and unpaid interest and liquidated damages, if any, to, but excluding, the date of purchase, on September 15, 2008, 2013 or 2018, or if any fundamental change defined in this prospectus occurs.

        The debentures will be evidenced by one or more global securities deposited with a custodian for and registered in the name of a nominee of The Depository Trust Company. Except as described in this prospectus, beneficial interests in the global securities will be shown on, and transfers thereof will be effected only through, records maintained by The Depository Trust Company and its direct and indirect participants.

        We do not intend to apply for listing of the debentures on any securities exchange or for inclusion of the debentures in any automated quotation system. The debentures are currently eligible for trading in The Portalsm Market of the National Association of Securities Dealers, Inc.

        We have agreed pursuant to a registration rights agreement to file a shelf registration statement permitting the registered resale of the debentures and the common stock issuable upon conversion of the debentures. If we fail to comply with specified obligations under the registration rights agreement, we must pay liquidated damages on the debentures. See "Description of Debentures—Registration rights".

        INVESTING IN THE DEBENTURES OR THE COMMON STOCK ISSUABLE UPON THEIR CONVERSION INVOLVES A HIGH DEGREE OF RISK. SEE "RISK FACTORS" BEGINNING ON PAGE 5.

        NEITHER THE SECURITIES AND EXCHANGE COMMISSION NOR ANY STATE SECURITIES COMMISSION HAS APPROVED OR DISAPPROVED OF THESE SECURITIES OR PASSED UPON THE ADEQUACY OR ACCURACY OF THIS PROSPECTUS. ANY REPRESENTATION TO THE CONTRARY IS A CRIMINAL OFFENSE.

Date of this prospectus is July 1, 2004



TABLE OF CONTENTS

 
  Page
PROSPECTUS SUMMARY   1
RISK FACTORS   5
THE COMPANY   9
USE OF PROCEEDS   10
DESCRIPTION OF DEBENTURES   11
DESCRIPTION OF COMMON STOCK   27
CERTAIN U.S. FEDERAL INCOME TAX CONSIDERATIONS   28
SELLING SECURITY HOLDERS   31
PLAN OF DISTRIBUTION   35
LEGAL MATTERS   36
INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM   36
NOTE REGARDING FORWARD-LOOKING STATEMENTS   37
WHERE YOU CAN FIND MORE INFORMATION   39
CERTAIN DOCUMENTS INCORPORATED BY REFERENCE   39

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PROSPECTUS SUMMARY

        The items in the following summary are described in more detail later in this prospectus and in the documents incorporated by reference. This summary provides an overview of selected information and does not contain all the information you should consider. Therefore, you should also read the entire prospectus, the more detailed information set out or incorporated by reference into this prospectus before making an investment.

        Unless the context otherwise requires, in this prospectus, the "Company", "Bristol-Myers Squibb", "we", "us" and "our" refer to Bristol-Myers Squibb Company and its subsidiaries.

Issuer   Bristol-Myers Squibb Company.
Debentures   $1,200,000,000 aggregate principal amount of the Floating Rate Convertible Senior Debentures due 2023.
Offering Price   Market price; the price at the initial offering was 100% of the principal amount of each debenture plus accrued interest, if any, from October 1, 2003. The principal amount per debenture is $1,000.
Maturity   September 15, 2023.
Ranking   The debentures are our senior unsecured obligations and rank equally in right of payment with all of our existing and future senior and unsecured indebtedness and senior to all our subordinated debt. The debentures effectively rank junior to any of our secured debt. In addition, the debentures are structurally subordinated to all liabilities of our subsidiaries, including trade payables.
    As of May 31, 2004, the aggregate amount of outstanding Company debt was $10.1 billion. As of the same date, the amount of such outstanding Company debt that was senior and unsecured was $10.1 billion, the amount of such outstanding issuer debt that was secured was immaterial and the amount of such outstanding Company debt that was debt of the Company's subsidiaries having claims against such subsidiaries' assets superior to any such claims of the debentures was $278 million.
Interest   The debentures will bear interest at an annual rate equal to 3-month LIBOR, reset quarterly, minus 0.50%, except that interest for any period will never be less than 0% and interest for the initial interest period to but excluding December 15, 2003 will be 0.64%. Interest will be payable quarterly in arrears on March 15, June 15, September 15 and December 15 of each year, each an "interest payment date", beginning December 15, 2003.
Conversion Rights and Conversion Rate   The holders may at any time prior to maturity convert the debentures into shares of our common stock at a conversion rate per $1,000 principal amount of debentures determined as follows:
         

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    For any conversion prior to September 15, 2008:
      if the applicable stock price is less than or equal to the base conversion price, the conversion rate will be the base conversion rate; and
      if the applicable stock price is greater than the base conversion price, the conversion rate will be determined in accordance with the following formula:
Base Conversion Rate + [(Applicable Stock Price-Base Conversion Price) × Incremental Share Factor]
    Applicable Stock Price
    except that the conversion rate will not exceed the maximum conversion rate described below.
    For any conversion on or after September 15, 2008, the conversion rate will be fixed at the conversion rate determined as set forth above assuming a conversion date that is eight trading days prior to September 15, 2008, which we refer to as the fixed conversion rate.
    For purposes of the foregoing:
      "applicable stock price" is equal to the average of the closing sale prices of our common stock over the five trading day period starting the third trading day following the conversion date of the debentures;
      "base conversion rate" is 24.2248;
      "base conversion price" is a dollar amount (initially $41.28) equal to $1,000 (the principal amount per debenture) divided by the base conversion rate;
      "incremental share factor" is 15; and
      "maximum conversion rate" is 38.7597.
    The conversion rate and the numbers that go into its calculation are subject to adjustment as described under "Description of Debentures—Conversion rate adjustments".
Redemption of Debentures at Our Option   At any time on or after September 21, 2008, we may redeem for cash all or a portion of the debentures, at a price equal to 100% of the principal amount plus accrued and unpaid interest and liquidated damages, if any, to, but excluding, the date of redemption. Holders may convert their debentures after they are called for redemption at any time prior to the close of business on the business day immediately preceding the redemption date. See "Description of Debentures—Redemption of debentures at our option".
Purchase of Debentures by Us at the Option of the Holder on Specified Dates   Holders may require us to purchase for cash all or a portion of their debentures, at a price equal to 100% of the principal amount plus accrued and unpaid interest and liquidated damages, if any, to, but excluding, the date of purchase, on September 15, 2008, 2013 or 2018. See "Description of Debentures—Purchase of debentures by us at the option of the holder".
         

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Purchase of Debentures by Us at the Option of the Holder Upon a Fundamental Change   Holders may require us to purchase for cash all or a portion of their debentures on a purchase date specified by us within 35 business days following a fundamental change, at a price equal to 100% of the principal amount plus accrued and unpaid interest and liquidated damages, if any, to, but excluding, the date of purchase, if any fundamental change occurs.
    A "fundamental change" is deemed to have occurred at such time as:
      any person, including its affiliates and associates, other than Bristol-Myers Squibb, its subsidiaries or their employee benefit plans, files a Schedule 13D or 14D-1 (or any successor schedule, form or report under the Exchange Act) disclosing that such person has become the beneficial owner of 50% or more of the voting power of our common stock or other capital stock into which the common stock is reclassified or changed, with some exceptions; or
      any transaction or event is consummated in connection with which all or substantially all of our common stock is exchanged for, converted into, acquired for or constitutes solely the right to receive consideration that is not all or substantially all common stock that: (i) is listed on, or immediately after the transaction or event will be listed on, a United States national securities exchange; or (ii) is approved, or immediately after the transaction or event will be approved, for quotation on the NASDAQ National Market or any similar United States system of automated dissemination of quotations of securities prices.
    A fundamental change will not be deemed to have occurred in respect of the foregoing, however, if the last reported sale price of our common stock for any five trading days within the ten consecutive trading days ending immediately before the later of the fundamental change or public announcement thereof equals or exceeds 105% of the conversion price of the debentures immediately before the fundamental change or the public announcement thereof.
Sinking Fund   None.
Registration Rights   We are obligated to use reasonable best efforts to cause the shelf registration statement to be declared effective by the SEC as soon as possible and, in any event, within 90 days of the filing, and to use reasonable best efforts to keep the shelf registration statement effective until the earlier of:
      the sale pursuant to Rule 144 under the Securities Act or the shelf registration statement of all the securities registered thereunder; and
         

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      the expiration of the Rule 144(k) holding period applicable to such securities held by persons that are not our affiliates.
    If we fail to comply with some obligations under the registration rights agreement, we will pay liquidated damages to the holders of the debentures. See "Description of Debentures—Registration rights".
DTC Eligibility   The debentures will be issued in book entry form and will be represented by two or more permanent global certificates deposited with a custodian for, and registered in the name of a nominee of, The Depository Trust Company, or DTC, in New York, New York. Beneficial interests in any such securities will be shown on, and transfers will be effected only through, records maintained by DTC and its direct and indirect participants. Any such interest may not be exchanged for certificated securities, except in limited circumstances. See "Description of Debentures—Book entry system".
Trading of Debentures   The debentures are expected to be eligible for trading in The PORTALsm Market of the National Association of Securities Dealers, Inc.
Use of Proceeds   We will not receive any proceeds from the sale of the debentures or the underlying common stock by the selling security holders.
NYSE Symbol of Bristol-Myers Common Stock   "BMY"
Ratings   As of the date of the Prospectus, Standard & Poor's Rating Group has given the notes a debt rating of "AA", with a negative outlook, and Moody's Investors Service has given the notes a debt rating of "A1", with a negative outlook.
 
   
  Year Ended December 31,
 
  Q1 2004
  2003
  Restated
2002

  Restated
2001

  Restated
2000

  Restated
1999

Ratio of Earnings to Fixed Charges(1)   18.02   13.91   7.54   10.64   36.48   28.11

(1)
We compute the ratio of earnings to fixed charges by dividing earnings by fixed charges. "Earnings" consists of income from continuing operations before provision for minority interests and income taxes, one-third of rents (deemed by the Company to be a reasonable approximation of the interest factor of such rental expense), interest and debt expense, net of amounts capitalized and amortized. "Fixed Charges" consists of one-third of rents, interest and debt expense and capitalized interest.

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RISK FACTORS

Risks Related to the Company

Over the next several years, we expect significant declines in net sales of some of our products which have lost or will lose market exclusivity protection.

        We cannot assure you that expected declines in net sales of our products which have lost or will lose market exclusivity protection and the corresponding increased competition from the sale of generic pharmaceutical products will not be material to our results of operations and cash flows.

        We have estimated declines in net sales for 2004 in the range of $1.2 to $1.3 billion from the 2003 levels for products, which have lost or will lose exclusivity protections in 2003 or 2004, specifically the metformin franchise (GLUCOPHAGE*/GLUCOVANCE*) in the United States, TAXOL® in Europe, MONOPRIL in the United States and Canada, Pravastatin in certain countries in Europe, PARAPLATIN in the United States and SERZONE in the United States.

        Substantial incremental exclusivity losses are expected in each of 2005 to 2007 representing continuing declines in sales of the products described above for 2003 and 2004, and additional declines attributable to loss of exclusivity protection primarily for PRAVACHOL in the United States (2006), MONOPRIL in Europe (2001-2008), ZERIT in Europe (2007-2011), CEFZIL (U.S. 2005; EU 2004-2009) and VIDEX/VIDEX EC (2004-2009—license on patent expiring in 2007 became non-exclusive in 2001 though not other licenses have yet been granted). Information on the dates of loss of exclusivity protection and sales for the most recent year for our major products is set forth in Item 1. Business of its Form 10-K Annual Report for 2003, and interim sales information is included in the Company's Form 10-Q Quarterly Report for the period ended March 31, 2004. The timing and amounts of sales reductions from exclusivity losses, their realization in particular periods and the eventual levels of remaining sales revenues are uncertain and dependent on the levels of sales at the time exclusivity protection ends, the timing and degree of development of generic competition (speed of approvals, market entry and impact) and other factors.

        PRAVACHOL, a cholesterol-reducing HMG CoA reductase inhibitor (statin), was the Company's largest product ranked by net sales in 2003 ($2.8 billion). While the product has begun to lose exclusivity in some markets, between now and its anticipated loss of U.S. exclusivity in 2006, its expected rate of decline in market share could be accelerated by the recently reported results of clinical studies. PRAVACHOL has been the subject of numerous clinical trials that have demonstrated that PRAVACHOL, when combined with a hearthealthy diet and exercise, reduces the risk of first heart attack in patients with elevated cholesterol and no clinical evidence of coronary heart disease and also reduces the risk of a subsequent cardiovascular event in patients with normal to moderately elevated cholesterol and clinical evidence of coronary heart disease. A recent clinical study sponsored by a competitor found that treatment with the competitor's statin resulted in no progression of atherosclerotic disease compared to treatment with PRAVACHOL which showed some progression, as demonstrated intravascular ultrasound. Another recent study sponsored by the Company found that acute coronary syndrome patients treated within ten days of their event benefited more from intensive statin therapy with a competitor's product than from standard statin therapy with PRAVACHOL in the reduction of the risk of later major cardiovascular events. Since the release of the most recent of these studies in early March 2004, PRAVACHOL has experienced a modest decline in U.S. prescription market share, consistent with market share declines for PRAVACHOL in recent prior periods during which there was growth in sales of competitive products including a new product launch.

        We also expect to have growth opportunities over the next several years. The opportunities include expected growth from in-line, recently launched and potential new products. Expectations of continued sales growth are subject to the outcome of the previously disclosed PLAVIX* patent litigation, and risks of product development and regulatory approval.

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        Net sales of PLAVIX* were approximately $2.5 billion in 2003 and are expected to grow substantially over the next several years. The Company anticipates that this revenue growth will be an important factor in offsetting expected decreases in sales of the Company's other products that recently have or will experience exclusivity losses during this period. Our U.S. territory partnership under our alliance with Sanofi-Synthelabo is a plaintiff in two pending patent infringement lawsuits related to the composition of matter patent for PLAVIX* (clopidogrel), which expires in 2011, based on the defendants seeking FDA approval to sell generic clopidogrel prior to the expiration of the composition of matter patent. If the composition of matter patent is found not infringed, invalid and/or unenforceable at the district court level, the FDA could then approve the defendants' sale of generic clopidogrel, and generic competition for PLAVIX* could begin, before we have exhausted our appeals. Such generic competition would likely result in substantial decreases in the sales of PLAVIX* in the United States. Although the plaintiffs intend to vigorously pursue enforcement of their patent rights in PLAVIX*, it is not possible at this time reasonably to assess the outcome of these lawsuits, or, if the Company were not to prevail in these lawsuits, the timing of potential generic competition for PLAVIX*. However, if such generic competition were to occur, the Company believes it is very unlikely to occur before sometime in the year 2005. It also is not possible reasonably to estimate the impact of these lawsuits on the Company. However, loss of market exclusivity of PLAVIX* and the subsequent development of generic competition would be material to the Company's sales of PLAVIX* and results of operations and cash flows and could be material to its financial condition and liquidity.

Lawsuits, claims, proceedings and investigations pending against us and certain of our subsidiaries are reasonably likely to be material to our results of operations and cash flows.

        We and our subsidiaries are the subject of a number of significant pending lawsuits, claims, proceedings and investigations. These matters involve securities, patent infringement, the Employee Retirement Income Security Act of 1974, as amended (ERISA), pricing, sales and marketing practices, antitrust, environmental, health and safety matters, product liability and insurance coverage. It is not possible at this time to reasonably assess the final outcome of these matters. There can be no assurance that there will not be an increase in the scope of any pending lawsuits, claims, proceedings and investigations or that any future lawsuits, claims, proceedings or investigations will not be material.

        We continue to believe, as previously disclosed, that during the next few years, the aggregate impact, beyond current reserves, of these and other legal matters affecting us is reasonably likely to be material to our results of operations and cash flows, and may be material to our financial condition and liquidity.

Risks Related to the Debentures

No public market exists for the debentures, and the resale of the debentures is subject to significant restrictions as well as uncertainties regarding the existence of any trading market for the debentures.

        The debentures are a new issue of securities for which there is currently no public market. We do not intend to list the debentures on any national securities exchange or automated quotation system. In addition, both the liquidity and the market price quoted for the notes may be adversely affected by changes in the overall market for securities and by changes in our financial performance or prospects, or in the prospects for the companies in our industry generally. We cannot assure you that an active or sustained trading market for the debentures will develop or continue for the debentures or that the holders will be able to sell their debentures. Although the initial purchasers informed us that they intended to make a market in the debentures after the initial private placement offering was completed, the initial purchasers are not required to make a market and may cease their market making at any time and without notice.

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        Moreover, even if a market does develop for the notes, they may trade at a price above or below either their purchase price or their face value. Future trading prices of the debentures will depend on many factors, including, among other things, prevailing interest rates, our operating results, the price of our common stock and the market for similar securities. Additionally, it is possible that the market for the debentures will be subject to disruptions which may have a negative effect on the value of the debentures, regardless of our prospects or financial performance.

        Under the registration rights agreement applicable to the debentures, we are required to file, and to use reasonable best efforts to have declared effective, a shelf registration statement registering the debentures and our common stock issuable upon the conversion of the debentures and to keep the shelf registration statement continuously effective. However, we cannot assure you that we will be successful in having that registration statement declared effective. In addition, the registration rights agreement permits us to suspend use of that shelf registration statement from time to time. Any such suspension could delay a proposed sale of debentures and/or common stock, which could have an adverse impact on such a proposed sale.

The yield on the debentures cannot be determined at this time and may be lower than the yield on a standard debt security of comparable maturity and may be zero.

        The yield on the debentures is based on 3-month LIBOR, which is the London Interbank Offered Rate, minus 0.50%. At March 25, 2004, 3-month LIBOR was 1.11% per annum. The yield on the debentures will be reset every three months. If LIBOR is at or below 0.50% per annum at the start of any three-month period, no interest will accrue on the debentures for such three-month period.

        The amount we pay holders may be less than the return the holders could earn on other investments. The holder's yield may be less than the yield a holder would earn if it bought a standard senior debt security of Bristol-Myers Squibb with the same stated maturity date. Your investment may not reflect the full opportunity cost to you when you take into account factors that affect the time value of money.

A downgrade, suspension or withdrawal of the rating assigned by a rating agency to the debentures, if any, would cause the liquidity or market value of the debentures to decline significantly.

        Standard & Poor's Ratings Group ("S&P") has given the notes a debt rating of "AA", with a negative outlook, and Moody's Investors Service ("Moody's") has given the notes a debt rating of "A1", with a negative outlook. A negative outlook suggests that the rating may be lowered.

        S&P has ten general categories of "Long-Term Issuer Credit Ratings". The highest general rating category is "AAA" and the lowest general rating categories are "SD" and "D". A "AA" rating is S&P's second highest general category of rating and is defined by S&P as the issuer having a very strong capacity to meet its financial commitments and differs from the highest rated obligors only in a small degree." In conjunction with the general category rating, S&P also may provide a ratings outlook, which assesses the potential direction of a long-term credit rating over the intermediate to longer term. Where assigned, rating outlooks fall into the following five categories: Positive (a rating may be raised), Negative (a rating may be lowered), Stable (a rating is not likely to change), Developing (a rating may be raised or lowered) and N.M. (not meaningful).

        Moody's has nine general categories of "Long-Term Ratings". The highest general category rating is "Aaa" and the lowest general category rating is "C". Obligations rated "A" are Moody's third highest category rating and are defined by Moody's as upper-medium grade and subject to low credit risk." In addition, Moody's appends numerical modifiers "1", "2", and "3" to each general category rating from "Aa" through "Caa". The modifier "1" indicates that the obligation ranks in the higher end of its general rating category; the modifier "2" indicates a mid-range ranking; and the modifier "3" indicates

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a ranking in the lower end of that general rating category." In addition, Moody's provides a rating outlook, which is an opinion regarding the likely direction of a rating over the medium term. Where assigned, rating outlooks fall into the following four categories: Positive (POS), Negative (NEG), Stable (STA), and Developing (DEV—contingent upon an event). When an outlook has not been assigned to an eligible entity, NOO (No Outlook) may be displayed.

        Since July 2002, our S&P long-term debt rating has declined from "AAA" to "AA", with a negative outlook, and our Moody's long-term debt rating has declined from "Aaa" to "A1", with a negative outlook. There have not been any changes in our long-term debt rating since July 2003 in the case of S&P and April 2003 in the case of Moody's. These rating declines have had only a marginal adverse impact on the cost of our borrowings.

        There can be no assurance that any rating assigned to the notes will remain for any given period of time or that a rating will not be lowered or withdrawn entirely by a rating agency.

We may not have the ability to raise the funds necessary to finance the purchase of the debentures if required by holders pursuant to the indenture.

        Upon the occurrence of certain specific kinds of fundamental changes, we will be required to offer to purchase all outstanding debentures. However, certain important corporate events, such as leveraged recapitalizations, that would increase the level of our indebtedness, may not constitute a "fundamental change" under the debentures. See "Description of Debentures—Fundamental change requires purchase of debentures by us at the option of the holder". In addition, we will be required to repurchase all or a portion of the outstanding debentures at the option of the holders on September 15, 2008, 2013 and 2018 and to repay all outstanding debentures at maturity in 2023. However, we might not have sufficient funds available at any such time to make the required repurchase of debentures, and restrictions in our other indebtedness outstanding in the future may affect our ability to make any such repurchase.

The fundamental change provision of the indenture governing the debentures may deter potential acquirors and will restrict our ability to effect some types of recapitalization transactions.

        Under the indenture governing the debentures, we will be required to offer to purchase all of the outstanding debentures for cash upon the occurrence of some fundamental changes. This provision could have the effect of making it more difficult for a third party to acquire, or of discouraging a third party from attempting to acquire, us. For example, a potential acquiror could not pay cash or a combination of unlisted stock and cash in exchange for all of our outstanding shares of our common stock without triggering the fundamental change provision. In addition, this fundamental change provision will limit our ability to effect some types of recapitalization structures. See "Description of Debentures—Fundamental change requires purchase of debentures by us at the option of the holder".

Holders of the debentures will be deemed to receive a taxable dividend upon some conversion rate adjustments.

        Holders of the debentures will be deemed to receive a taxable dividend if the conversion rate of the debentures is adjusted to reflect a change in the quarterly dividend we pay to holders of our common stock or in some other circumstances described under "Description of Debentures—Conversion rate adjustments". Holders of the debentures may also be deemed to receive a taxable dividend if there is an increase in the conversion rate pursuant to the formula described under "Description of Debenture—Conversion rights".

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We cannot assure you that an active trading market will develop for the debentures.

        There has been no public market for the debentures. In addition, both the liquidity and the market price quoted for the debentures may be adversely affected by changes in the price of our common stock, changes in the overall market for convertible securities and by changes in our financial performance or prospects, or in the prospects for companies in our industry generally. In particular, the price of the debentures may fluctuate with our stock price since the debentures are convertible into stock. As a result, we cannot assure you that an active or stable trading market will develop or continue for the debentures.


THE COMPANY

        Bristol-Myers Squibb Company was incorporated under the laws of the State of Delaware in August 1933 under the name Bristol-Myers Company, as successor to a New York business started in 1887. In 1989, the Bristol-Myers Company changed its name to Bristol-Myers Squibb Company as a result of a merger. The Company, through its divisions and subsidiaries, is engaged in the discovery, development, licensing, manufacturing, marketing, distribution and sale of pharmaceuticals and other healthcare related products.

        The Company has four reportable segments—Pharmaceuticals, Oncology Therapeutics Network (OTN), Nutritionals and Other Healthcare. The Pharmaceuticals segment is comprised of the global pharmaceutical and international (excluding Japan) consumer medicines business. The OTN segment provides oncology products, supportive care products and related supplies to office-based oncologists in the United States. The Nutritionals segment consists of Mead Johnson Nutritionals (Mead Johnson), primarily an infant formula business. The Other Healthcare segment consists of ConvaTec, Medical Imaging and Consumer Medicines (North America and Japan) businesses.

        The Pharmaceuticals segment discovers, develops, licenses, manufactures, markets, distributes and sells branded pharmaceuticals. These products are sold worldwide, primarily to wholesalers, retail pharmacies, hospitals, government entities and the medical profession. The Company manufactures these products in the United States and Puerto Rico and in fifteen foreign countries. Pharmaceuticals sales accounted for approximately 71% of the Company's sales in 2003 and in 2002 and 75% of the Company's sales in 2001. Most of the Company's pharmaceutical revenues come from products in the following therapeutic classes: cardiovascular and metabolic, oncology, infectious disease, including human immunodeficiency virus/acquired immune deficiency syndrome (HIV/AIDS), and affective (psychiatric) disorders.

        Selected products from continuing operations are as follows:

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*
Indicates, in this prospectus, brand names of products which are registered trademarks not owned by BMS. ERBITUX is a trademark of ImClone Systems Incorporated, AVAPRO/AVALIDE and PLAVIX are trademarks of Sanofi-Synthelabo S.A. and ABILIFY is a trademark of Otsuka Pharmaceutical Company, Ltd.

        Our principal executive offices are located at 345 Park Avenue, New York, New York 10154, and our telephone number is (212) 546-4000. Our website is located at www.bms.com. The information on our website is not incorporated by reference in this offering circular.


USE OF PROCEEDS

        We will not receive any proceeds from the sale of the debentures or the underlying common stock by the selling security holders.

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DESCRIPTION OF DEBENTURES

        The following summary does not purport to be complete, and is subject to, and is qualified in its entirety by reference to, all of the provisions of the debentures and the indenture. We urge you to read the indenture and the form of the debentures, which you may obtain from us upon request, because they and not this description define your rights in respect of the debentures.

General

        We issued the debentures under an indenture, dated as of October 1, 2003, between us and JPMorgan Chase Bank, as trustee.

Principal amount, maturity and interest

        The debentures were limited to $1.2 billion aggregate principal amount ($200 million of which was issued upon exercise of the initial purchasers' purchase option) and were issued in registered form without coupons in denominations of $1,000 principal amount and any integral multiple of $1,000 above that amount. We use the term "debenture" in this prospectus to refer to each $1,000 principal amount of debentures. The debentures will mature on September 15, 2023.

        The debentures bear interest at an annual rate equal to 3-month LIBOR, reset quarterly, minus 0.50%, except that interest for any period will never be less than 0% and interest for the initial interest period to but excluding December 15, 2003 bore 0.64%. Interest on the debentures will accrue from October 1, 2003 or from the most recent date to which regular interest has been paid or provided for and will be payable quarterly in arrears on March 15, June 15, September 15 and December 15 of each year, beginning December 15, 2003, to the person in whose name a debenture is registered at the close of business on the March 1, June 1, September 1 or December 1, as the case may be, immediately preceding the relevant interest payment date, each of which we refer to as a record date. Each payment of interest include interest accrued for the period, which we refer to as an interest period, commencing on and including the immediately preceding interest payment date (or, if none, October 1, 2003) to but excluding the applicable interest payment date. Interest on the debentures are computed using the actual number of days in the relevant interest period divided by 360. Holders of debentures may also be entitled to receive liquidated damages under the circumstances described below under "—Registration rights".

        If any interest payment date of a debenture falls on a day that is not a business day, such interest payment date will be postponed to the next succeeding business day. If the stated maturity date, redemption date or other date on which we are required to repurchase debentures at the option of any holder would fall on a day that is not a business day, the required payment of interest, if any, and principal will be made on the next succeeding business day and no interest on such payment will accrue for the period from and after such date to such next succeeding business day. The term "business day" means any day (other than a day which is a Saturday, Sunday or legal holiday in the State of New York) on which banks are open for business in New York, New York, provided such a day is also a London banking day. The term "London banking day" means a day on which commercial banks are open for business, including dealings in United States dollars, in London.

        The debentures are redeemable prior to maturity only on or after September 21, 2008 and as described below under "—Redemption of debentures at our option", and do not have the benefit of a sinking fund. Principal of and interest and liquidated damages, if any, on the debentures will be payable at the office of the trustee. The debentures may be presented for conversion at the office of the trustee, and for registration of transfer or exchange at the office of the registrar, which initially will be JPMorgan Chase Bank, 4 New York Plaza, 15th Floor, New York, New York 10004. No service charge will be made for any registration of transfer or exchange of debentures, but we may require payment of a sum sufficient to cover any tax or other governmental charge payable in connection therewith.

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        Maturity, conversion, purchase by us at the option of a holder or redemption of a debenture will cause interest to cease to accrue on such debenture. We may not reissue a debenture that has matured or been converted, purchased by us at the option of a holder, redeemed or otherwise canceled, except for registration of transfer, exchange or replacement of such debenture.

        Holders will be deemed to receive a distribution subject to U.S. federal income tax as a dividend if the conversion rate is adjusted to reflect a change in the quarterly dividend we pay to holders of common stock or in certain other situations requiring a conversion rate adjustment. See "Certain U.S. Federal Income Tax Considerations".

        The annual rate of interest payable on the debentures will be reset on each March 15, June 15, September 15 and December 15, commencing December 15, 2003, and we refer to each of those dates as a LIBOR reset date. If any LIBOR reset date would otherwise be a day that is not a business day, that LIBOR reset date will be postponed to the next succeeding business day.

        A calculation agent, initially JPMorgan Chase Bank, will determine 3-month LIBOR with respect to each interest period after the initial interest period, based on the following definition.

        "3-month LIBOR" for any interest period that begins on a particular LIBOR reset date means:

        "Money Telerate Page 3750" means the display on Moneyline Telerate (or any successor service) on such page (or any other page as may replace such page on such service) for the purpose of displaying the London interbank rates of major banks for United States dollars.

Ranking

        The debentures are our senior unsecured obligations and rank equally in right of payment with all of our existing and future senior unsecured indebtedness. The debentures effectively rank junior to any of our secured debt and are structurally subordinated to the indebtedness and other liabilities of our subsidiaries, including trade payables.

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        As of May 31, 2004, the aggregate amount of outstanding Company debt was $10.1 billion. As of the same date, the amount of such outstanding Company debt that was senior and unsecured was $10.1 billion, the amount of such outstanding issuer debt that was secured was immaterial and the amount of such outstanding Company debt that was debt of the Company's subsidiaries having claims against such subsidiaries' assets superior to any such claims of the debentures was $278 million.

Conversion rights

        At any time prior to maturity, a holder may convert each $1,000 principal amount of debentures into a number of shares of our common stock equal to the conversion rate.

        Prior to September 15, 2008, the conversion rate will be determined as follows:

Base Conversion Rate + [(Applicable Stock Price - Base Conversion Price) × Incremental Share Factor]
Applicable Stock Price

        From and after September 15, 2008, the conversion rate will be fixed for the remainder of the term of the debentures at the conversion rate determined as set forth above assuming a conversion date that is eight trading days prior to September 15, 2008, which we refer to as the fixed conversion rate.

        For purposes of the foregoing:

        The conversion rate and the numbers that go into its calculation are subject to adjustment as described under "—Conversion rate adjustments".

        We will not deliver any fractional shares of our common stock upon conversion of the debentures. In lieu of a fractional share otherwise deliverable in respect of debentures being converted by a holder (calculated on an aggregate basis), the holder will be entitled to receive an amount of cash equal to the fraction of a share times the applicable stock price.

Conversion procedures

        To convert your debenture for our common stock, you must do the following (or comply with DTC procedures for doing so in respect of your beneficial interest in debentures evidenced by a global debenture):

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        Pursuant to the indenture, the date on which all of the foregoing requirements have been satisfied is the conversion date.

        Upon conversion of debentures, a holder will not receive any cash payment of interest (unless such conversion occurs between a regular record date and the interest payment date to which it relates). Our delivery to the holder of the full number of shares of our common stock for which the debenture is convertible, together with any cash payment for such holder's fractional shares, will be deemed:

        As a result, the principal amount and unpaid interest through the conversion date are deemed to be paid in full rather than canceled, extinguished or forfeited.

        Notwithstanding the above, if debentures are converted after a record date but prior to the next succeeding interest payment date, holders of such debentures at the close of business on the record date will receive the interest payable on such debentures on the corresponding interest payment date notwithstanding the conversion. Such debentures, upon surrender for conversion, must be accompanied by funds equal to the amount of interest payable on the debentures so converted; provided that no such payment need be made (1) if we have specified a redemption date that is after a record date and on or prior to the next interest payment date, (2) if we have specified a fundamental change purchase date that is after a record date and on or prior to the next interest payment date or (3) to the extent of overdue interest, if any, that exists at the time of conversion with respect to such debenture.

        Shares of our common stock and cash in lieu of fractional shares deliverable upon conversion will be delivered through the trustee no later than the third business day following the determination of the applicable stock price.

        For a discussion of the tax treatment of a holder converting debentures, see "Certain U.S. Federal Income Tax Considerations—U.S. holders—conversion of debentures".

Conversion rate adjustments

        The conversion rate and the numbers that go into its calculation will be adjusted for:

in the event that we make a distribution to all holders of our common stock consisting of capital stock of, or similar equity interests in, one of our subsidiaries or other business units, the conversion rate will

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be adjusted based on the market value of the securities so distributed relative to the market value of our common stock, in each case based on the average closing sale prices of those securities for the ten trading days commencing on and including the fifth trading day after the date on which "ex-dividend trading" commences for such dividend or distribution on the New York Stock Exchange or such other national or regional exchange or market on which the securities are then listed or quoted;

however, the adjustment referred to in this clause will generally not be made if as of the closing of the offer, the offering documents disclose a plan or an intention to cause us to engage in a consolidation or merger of Bristol-Myers Squibb or a sale of all or substantially all of our assets.

        To the extent that we adopt a rights plan during the term of the debentures, you will receive, upon conversion of your debentures, in addition to our common stock, the rights under the rights plan unless, prior to the conversion, the rights have expired, terminated or been redeemed or unless the rights have separated from our common stock, in which case the conversion rate will be adjusted at the time of separation as if we distributed to all holders of our common stock shares of our capital stock, evidences of indebtedness or assets as described under the fourth bullet point above, subject to readjustment in the event of the subsequent expiration, termination or redemption of such rights.

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        In the event of:

        You will in some situations described above be deemed to receive a distribution subject to United States federal income tax as a dividend if the conversion rate is adjusted to reflect a change in the quarterly dividend we pay to holders of our common stock or in some other situations requiring a conversion rate adjustment. See "Certain U.S. Federal Income Tax Considerations".

        We may, from time to time, increase the conversion rate for a period of at least 20 business days if our board of directors has made a determination that this increase would be in our best interests. Any such determination by our board will be conclusive. We would give holders at least 15 days' notice of any increase in the conversion rate. In addition, we may increase the conversion rate if our board of directors deems it advisable to avoid or diminish any income tax to holders of our common stock resulting from any stock or rights distribution. See "Certain U.S. Federal Income Tax Considerations".

        We will not be required to make an adjustment in the conversion rate unless the adjustment would require a change of at least 1% in the conversion rate. However, we will carry forward any adjustments that are less than 1% of the conversion rate.

        Except as described above in this section, we will not adjust the conversion rate for any issuance of our common stock or convertible or exchangeable securities or rights to purchase our common stock or convertible or exchangeable securities.

        We or the calculation agent will be responsible for making all calculations called for under the debentures. These calculations include, but are not limited to, determinations of the market price of our common stock, accrued interest payable on the debentures and the conversion rate (and any adjustments thereto) or the conversion price of the debentures. We will make all calculations in good faith, and absent manifest error, our calculations will be final and binding on holders of debentures. We will provide a schedule of calculations to the trustee and the trustee is entitled to rely upon the accuracy of such calculations without independent verification. The trustee will forward these calculations to any holder of debentures upon the request of that holder.

Redemption of debentures at our option

        Prior to September 21, 2008, the debentures will not be redeemable at our option. Beginning on September 21, 2008 and thereafter, we may redeem the debentures at any time as a whole, or from time to time in part, for a cash redemption price equal to 100% of the principal amount plus accrued and unpaid interest and liquidated damages, if any, to, but excluding, the date fixed for redemption. We will give not less than 30 days, nor more than 60 days, notice of redemption by mail to holders of the debentures.

        If we decide to redeem fewer than all of the outstanding debentures, the trustee may select the debentures by lot, pro rata, or by another method the trustee considers fair and appropriate. If the trustee selects a portion of your debentures for partial redemption and you convert a portion of your debentures, the converted portion will be deemed, to the extent practicable, to be the portion selected for redemption.

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        If we have given a redemption notice as provided in the indenture and the trustee holds on the date fixed for redemption money sufficient to pay the redemption price for all debentures called for redemption, those debentures will cease to bear interest on the date fixed for redemption and after that date the only right of the holders of those debentures will be to receive payment of the redemption price upon surrender of those debentures as provided in the indenture.

Purchase of debentures by us at the option of the holder

        You have the right to require us to purchase all or a portion of your debentures on September 15, 2008, 2013 or 2018, or if any such day is not a business day, on the immediately succeeding business day, each such day a "purchase date", for a cash purchase price equal to 100% of the principal amount plus accrued and unpaid interest and liquidated damages, if any, to, but excluding, the applicable purchase date. At our sole discretion, we may also add additional dates on which you may require us to purchase all or a portion of your debentures. However, we cannot assure you that we will add any purchase dates. You may submit your debentures for purchase to the trustee at any time from the opening of business on the date that is 21 business days prior to the purchase date until the close of business on the purchase date. Our ability to satisfy our purchase obligations may be affected by the factors described in "Risk Factors—Risks Related to the Debentures. We may not have the ability to raise the funds necessary to finance the purchase of the debentures if required by holders pursuant to the indenture".

        We will be required to give notice on a date not less than 21 business days prior to each purchase date to all holders at their addresses shown in the register of the registrar, and to beneficial owners as required by applicable law, describing, among other things, the procedures that holders must follow to require us to purchase their debentures.

        If we have received your notice requiring us to purchase your debentures as provided in the indenture and the trustee holds on the applicable purchase date money sufficient to pay the redemption price for those debentures, those debentures will cease to bear interest on that purchase date and after that date your only right with respect to those debentures will be to receive payment of the purchase price upon surrender of those debentures as provided in the indenture.

        We will comply with any applicable provisions of Rule 13e-4 and any other tender offer rules under the Exchange Act in connection with the right of holders to require us to repurchase debentures on any purchase date.

Fundamental change requires purchase of debentures by us at the option of the holder

        If a fundamental change occurs at any time prior to the maturity of the debentures, you will have the right to require us to purchase all or a portion of your debentures, for a cash purchase price equal to 100% of the principal amount plus accrued and unpaid interest and liquidated damages, if any, to, but excluding, the fundamental change purchase date, unless the fundamental change purchase date falls after a record date and on or prior to the corresponding interest payment date, in which case we will pay the full amount of accrued and unpaid interest and liquidated damages, if any, payable on such interest payment date to the holder of record at the close of business on the corresponding record date. The fundamental change purchase date will be a business day specified by us that is not less than 20 nor more than 35 business days after the occurrence of the applicable fundamental change. You may submit your debentures for purchase to the trustee at any time from the opening of business on the date that is 21 business days prior to the purchase date until the close of business on the purchase date. Our ability to satisfy our purchase obligations may be affected by the factors described in "Risk Factors—Risks Related to the Debentures. We may not have the ability to raise the funds necessary to finance the purchase of the debentures if required by holders pursuant to the indenture".

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        Under our indenture, a "fundamental change" is deemed to have occurred at such time as:


A fundamental change will not be deemed to have occurred in respect of the foregoing, however, if the last reported sale price of our common stock for any five trading days within the 10 consecutive trading days ending immediately before the later of the fundamental change or public announcement thereof equals or exceeds 105% of the conversion price of the debentures immediately before the fundamental change or the public announcement thereof.

        Within 15 business days after the occurrence of a fundamental change, we will be required to give notice to the trustee and to all holders of debentures at their addresses shown in the register of the registrar, and to beneficial owners as required by applicable law, summarizing the events causing the fundamental change and describing, among other things, the procedures that holders must follow to require us to purchase their debentures.

        If we have received your notice requiring us to purchase your debentures as provided in the indenture and the trustee holds on the applicable purchase date money sufficient to pay the redemption price for those debentures, those debentures will cease to bear interest on that purchase date and after that date your only right with respect to those debentures will be to receive payment of the purchase price upon surrender of those debentures as provided in the indenture.

        We will comply with any applicable provisions of Rule 13e-4 and any other tender offer rules under the Exchange Act in the event of a fundamental change.

Covenants

        We have agreed not to create, assume or suffer to exist, any mortgages or other liens upon any Restricted Property to secure any of our Debt or Debt of any Subsidiary or any other person, or permit any Subsidiary to do so, without securing the debentures equally and ratably with all other indebtedness secured by such liens. This covenant has some exceptions, which generally permit:

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        Neither we nor any Subsidiary owning Restricted Property may enter into any Sale and Leaseback Transaction unless we or such Subsidiary could incur Debt, in a principal amount at least equal to the Value of such Sale and Leaseback Transaction, which is secured by liens on the property to be leased without equally and ratably securing the outstanding senior debt securities without violating the "Limitation on Liens" covenant discussed above. We, or any such Subsidiary, may also enter into a Sale and Leaseback Transaction if, during the six months following the effective date of such Sale and Leaseback Transaction, we apply an amount equal to the Value of such Sale and Leaseback Transaction to the acquisition of Restricted Property or to the voluntary retirement of debt securities or Funded Debt. We will receive a credit toward the amount required to be applied to such retirement of indebtedness for the principal amount of any debt securities or Funded Debt delivered to the Trustee for retirement or cancellation during the six months immediately following the effective date of such Sale and Leaseback Transaction.

        The covenants described above only restrict our ability to place liens on, or enter into Sale and Leaseback Transactions in respect of, those manufacturing facilities in the United States which individually constitute 2% or more of our Consolidated Net Tangible Assets and which our board of directors believes are of material importance to our business. Because none of our manufacturing facilities located within the continental United States has been determined by our board of directors to be material, none of them currently meets the definition of Restricted Property. As a result, these covenants do not currently restrict us from securing indebtedness with any of our physical facilities or from entering into Sale and Leaseback Transactions with respect to any of our physical facilities, and if we did so, we would not be required to similarly secure the debentures.

        Other than the restrictions on liens and Sale and Leaseback Transactions described above, the indenture and the debentures do not contain any covenants or other provisions designed to protect holders of the debentures in the event of a highly leveraged transaction involving the Company.

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        "Consolidated Net Tangible Assets" means the total amount of our assets after deducting:

        In calculating the total amount of our assets, we must subtract applicable reserves and other properly deductible items. In calculating our current liabilities, we must exclude the amount of liabilities which are by their terms extendable or renewable at the option of the obligor to a date more than 12 months after the date as of which the amount is being determined.

        "Debt" means:

        "Funded Debt" means:

        The definition of Funded Debt only includes Debt incurred by us meeting one of the above requirements if it ranks at least equally with the senior debt securities.

        "Restricted Property" means:

        In this definition, "manufacturing facility" means property, plant and equipment used for actual manufacturing and for activities directly related to manufacturing. The definition excludes sales offices, research facilities and facilities used only for warehousing, distribution or general administration. The definition provides that no manufacturing facility, or portion thereof, shall be deemed of material importance if its gross book value before deducting accumulated depreciation is less than 2% of Consolidated Net Tangible Assets.

        "Sale and Leaseback Transaction" means any arrangement pursuant to which we or any Subsidiary leases any Restricted Property that has been or is to be sold or transferred by us or the Subsidiary to another person, other than:

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        "Subsidiary" means a corporation of which we or one or more corporations meeting this definition owns, directly or indirectly, the majority of the outstanding voting stock.

        "Value" means, with respect to a Sale and Leaseback Transaction, an amount equal to the present value of the lease payments remaining on the date as of which the amount is being determined, without regard to any renewal or extension options contained in the lease. To determine such present value, we use a discount rate equal to the weighted average interest rate on the debt securities of all series that (i) have the benefit of the covenant limiting Sale and Leaseback Transactions discussed above, (ii) are outstanding on the effective date of the Sale and Leaseback Transaction and (iii) are issued under our indenture, dated June 1, 1993, between us and JPMorgan Chase Bank, as trustee, as supplemented and amended from time to time (or, if there are no such series, the interest rate then being borne on your debentures).

Merger, consolidation or conveyance or transfer of assets

        We may not, without the consent of the holders of the debentures, merge into or consolidate with any other person, or convey or transfer all or substantially all of our properties and assets to another person, unless:

        The remaining or acquiring corporation will take over all of our rights and obligations under the indenture.

Events of default, notice and waiver

        The following events are defined in the indenture as "Events of Default":

        If an event of default occurs and continues, the trustee or the holders of at least 25% in principal amount of the debentures may declare the entire principal amount to be due and payable immediately.

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        The declaration may be annulled and past defaults may be waived by the holders of a majority in principal amount of the debentures if we satisfy certain conditions. However, payment defaults that are not cured may only be waived by all holders of debentures.

        The indenture requires the trustee to give the holders of debentures notice of a default within 90 days unless the default is cured or waived. However, the trustee may withhold this notice if it determines in good faith that it is in the interest of those holders. The trustee may not, however, withhold this notice in the case of a payment default.

        Other than its duties in case of an event of default, a trustee is not obligated to exercise any of its rights or powers under the indenture at the request or direction of any of the holders of debentures, unless the holders have offered to the trustee indemnification satisfactory to it.

        If such indemnification is provided, the holders of a majority in principal amount of outstanding debentures may, subject to certain limitations, direct the time, method and place of conducting any proceeding for any remedy available to the trustee, or exercising any trust or other power conferred on the trustee.

        The indenture includes a covenant that we will deliver within 120 days after the end of each fiscal year to the trustee a certificate of no default, or specifying the nature and status of any default that exists.

        Street name and other indirect holders should consult their banks and brokers for information on their requirements for giving notice or taking other actions upon a default.

Modification of the indenture

        Together with the trustee, we may, when authorized by our board of directors, modify the indenture without the consent of the holders for limited purposes, including but not limited to adding to our covenants or events of default and curing ambiguities.

        Together with the trustee, we may, when authorized by our board of directors, also make modifications and amendments to the indenture with the consent of the holders of a majority in principal amount of the outstanding debentures. However, without the consent of each affected holder, no modification may:

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Discharge of the indenture

        We may satisfy and discharge our obligations under the indenture by delivering to the trustee for cancellation all outstanding debentures or by depositing with the trustee after the debentures have become due and payable, whether at stated maturity, or any redemption date, or upon conversion or otherwise, cash or our common stock (as applicable under the terms of the indenture) sufficient to pay all of the outstanding debentures and paying all other sums payable by us under the indenture.

Relationship with the trustee

        We may from time to time maintain lines of credit, and have other customary banking relationships, with the trustee under the indenture.

Governing law

        The indenture and the debentures will be governed by and construed in accordance with the laws of the State of New York.

Book-entry system

        The debentures will be represented by one or more global securities. Each global security will be deposited with, or on behalf of, DTC and be registered in the name of a nominee of DTC.

        Except under circumstances described below, the debentures will not be issued in definitive form. Upon the issuance of a global security, DTC will credit on its book-entry registration and transfer system the accounts of persons designated by the initial purchasers with the respective principal amounts of the debentures represented by the global security. Ownership of beneficial interests in a global security will be limited to persons that have accounts with DTC or its nominee ("participants") or persons that may hold interests through participants. Owners of beneficial interests in the debentures represented by the global securities will hold their interests pursuant to the procedures and practices of DTC. Ownership of beneficial interests in a global security will be shown on, and the transfer of that ownership will be effected only through, records maintained by DTC or its nominee. The laws of some states require that certain purchasers of securities take physical delivery of such securities in definitive form. Such limits and such laws may impair the ability to transfer beneficial interests in a global security.

        So long as DTC or its nominee is the registered owner of a global security, DTC or its nominee, as the case may be, will be considered the sole owner or holder of the debentures represented by that global security for all purposes under the indenture. Except as provided below, owners of beneficial interests in a global security will not be entitled to have debentures represented by that global security registered in their names, will not receive or be entitled to receive physical delivery of debentures in definitive form and will not be considered the owners or holders thereof under the indenture. Beneficial owners will not be holders and will not be entitled to any rights provided to the holders of debentures under the global securities or the indenture. Principal payments, interest payments and liquidated damage payments, if any, on debentures registered in the name of DTC or its nominee will be made to DTC or its nominee, as the case may be, as the registered owner of the relevant global security. None of Bristol-Myers, the trustee or the registrar for the debentures will have any responsibility or liability for any aspect of the records relating to, or payments made on account of, beneficial interests in a global security or for maintaining, supervising or reviewing any records relating to such beneficial interests.

        We expect that DTC or its nominee, upon receipt of any payment of principal or interest, if any, will credit immediately participants' accounts with payments in amounts proportionate to their respective beneficial interests in the principal amount of the relevant global security as shown on the

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records of DTC or its nominee. We also expect that payments by participants to owners of beneficial interests in a global security held through such participants will be governed by standing instructions and customary practices, as is the case with securities held for the accounts of customers in bearer form or registered in "street name", and will be the responsibility of such participants.

        If we redeem less than all of the global security, we have been advised that it is DTC's practice to determine by lot the amount of the interest of each participant in the global security to be redeemed.

        Although DTC is expected to follow the foregoing procedures in order to facilitate transfers of interests in a global security among participants of DTC, it is under no obligation to perform or continue responsibility for the performance by DTC or its respective participants or indirect participants of their respective obligations under the rules and procedures governing their operations.

        If DTC is at any time unwilling or unable to continue as a depositary and a successor depositary is not appointed by us within 90 days or if an event of default will occur under the indenture, we will issue debentures in definitive form in exchange for the entire global security for the debentures. In addition, we may at any time and in our sole discretion determine not to have debentures represented by a global security and, in such event, will issue debentures in definitive form in exchange for the entire global security relating to such debentures. In any such instance, an owner of a beneficial interest in a global security will be entitled to physical delivery in definitive form of debentures represented by such global security equal in principal amount to such beneficial interest and to have such debentures registered in its name. Debentures so issued in definitive form will be issued as registered debentures in denominations of $1,000 principal amount and integral multiples thereof, unless otherwise specified by us.

        DTC has advised us that it is a limited-purpose trust company organized under the New York Banking Law, a "banking organization" within the meaning of the New York Banking Law, a member of the Federal Reserve System, a "clearing corporation" within the meaning of the New York Uniform Commercial Code, and a "clearing agency" registered pursuant to the provisions of Section 17A of the Exchange Act.

        DTC holds securities deposited with it by its participants and facilitates the settlement of transactions among its participants in such securities through electronic computerized book-entry changes in accounts of the participants, thereby eliminating the need for physical movement of securities certificates. DTC's participants include securities brokers and dealers, banks, trust companies, clearing corporations and certain other organizations, some of whom (and/or their representatives) own the depositary. Access to DTC's book-entry system is also available to others, such as banks, brokers, dealers and trust companies that clear through or maintain a custodial relationship with a participant, either directly or indirectly.

        According to DTC, the foregoing information with respect to DTC has been provided to the financial community for informational purposes only and is not intended to serve as a representation, warranty or contract modification of any kind.

Registration rights

        We have entered into a registration rights agreement with the initial purchasers. In the registration rights agreement, we agree, for the benefit of the holders of the debentures and the shares of our common stock issuable upon conversion of the debentures (the "registrable securities"), that we will, at our own expense:

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        We will be permitted to suspend the use of the prospectus that is part of the shelf registration statement in connection with the sales of registrable securities during prescribed periods of time for reasons relating to pending corporate developments, public filings with the SEC and other events. The periods during which we can suspend the use of the prospectus may not, however, exceed a total of 90 days in any 12-month period.

        We will provide to each holder of registrable securities copies of the prospectus that is a part of the shelf registration statement, notify each such holder when the shelf registration statement has been filed, notify each such holder when the shelf registration statement has become effective and take certain other actions required to permit public resales of the registrable securities.

        Additional interest referred to as "liquidated damages" will be paid to holders of debentures if a shelf registration statement for the debentures is not timely filed or declared effective or if the prospectus is unavailable for periods in excess of those permitted above. Such liquidated damages shall accrue until such failure to file or become effective or unavailability is cured on the debentures as follows:

        So long as failure to file or become effective or unavailability continues, liquidated damages will be paid in cash on each interest payment date for the debentures to the holder of record on the record date immediately preceding the applicable interest payment date. When such registration default is cured, accrued and unpaid liquidated damages will be paid in cash to the record holder as of the date of such cure.

        Liquidated damages will not be paid in excess of 0.50%, regardless of whether one or more registration defaults or effectiveness failures occur.

        A holder who elects to sell any registrable securities pursuant to the shelf registration statement:

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        We have provided a notice and questionnaire to the holders of registrable securities not less than 30 calendar days prior to the time the shelf registration statement is declared effective.

        No holder of registrable securities will be entitled:

        Holders of registrable securities will, however, have at least 28 calendar days from the date on which the notice and questionnaire was provided to return a completed and signed notice and questionnaire to us.

        Beneficial owners of registrable securities who have not returned a notice and questionnaire by the questionnaire deadline described above may receive another notice and questionnaire from us upon request. Following our receipt of a completed and signed notice and questionnaire, we will include the registrable securities covered thereby in the shelf registration statement as provided in the registration rights agreement. Once a shelf registration statement has become effective, we shall be obligated to file post-effective amendments by no later than the last business day of the month of February, April, June, August, October or December next occurring at least five business days after receipt by the Company of such notice and questionnaire.

        We will agree in the registration rights agreement to use our reasonable best efforts to cause the shares of common stock issuable upon conversion of the debentures to be listed on the New York Stock Exchange. However, if the common stock is not then listed on the New York Stock Exchange, we will use our reasonable best efforts to cause the shares of common stock issuable upon conversion of the debentures to be listed on whichever other stock exchange or trading system the common stock primarily trades on prior to the effectiveness of the shelf registration statement.

        This summary of certain provisions of the registration rights agreement is not complete and is subject to, and qualified in its entirety by reference to, all the provisions of the registration rights agreement, a copy of which will be made available to beneficial owners of the debentures upon request to us.

26



DESCRIPTION OF COMMON STOCK

        As of the date of this prospectus, we are authorized to issue up to 4,500,000,000 shares of common stock, par value $0.10 per share. As of June 25, 2004, 1,945,132,685 shares of common stock were outstanding. The common stock is listed on the New York Stock Exchange and the Pacific Exchange, Inc., under the symbol "BMY".

Dividends

        Holders of common stock are entitled to receive dividends out of any assets legally available for payment of dividends as may from time to time be declared by our board of directors, subject to the rights of the holders of the preferred stock. See "Dividend Policy".

Voting

        Each holder of common stock is entitled to one vote per share on all matters requiring a vote of the stockholders, including, without limitation, the election of directors. The holders of common stock do not have cumulative voting rights.

Rights upon liquidation

        In the event of our voluntary or involuntary liquidation, dissolution or winding up, the holders of common stock will be entitled to share equally in our assets available for distribution after payment in full of all debts and after the holders of preferred stock have received their liquidation preferences in full.

Board of directors

        Our Certificate of Incorporation provides that members of our board of directors shall be elected for one-year terms beginning with the election of directors in 2004. Formerly, our directors had been divided into three classes with each class serving three-year terms. Beginning in 2006, all directors will be elected for one-year terms. At any meeting of our board of directors, a total of five directors constitutes a quorum.

Supermajority vote for business combinations

        Our Certificate of Incorporation also provides that a number of business combinations must be approved by an affirmative vote of the holders of 75% of the then outstanding shares of our capital stock entitled to vote generally in the election of directors, voting together as a single class. A vote of approval is required for any of the following business combinations to which an interested stockholder beneficially owning more than ten percent of the voting stock or any of its affiliates is a party:


        The 75% vote of approval is not required if:

27


Miscellaneous

        Shares of common stock are not redeemable and have no subscription, conversion or preemptive rights.


CERTAIN U.S. FEDERAL INCOME TAX CONSIDERATIONS

        The following is a discussion of the material U.S. federal income tax consequences of the purchase, ownership and disposition of debentures and shares of our common stock acquired upon conversion of the debentures. The discussion is based on the Internal Revenue Code (the "Code"), Treasury regulations, judicial authorities, published positions of the Internal Revenue Service (the "IRS") and other applicable authorities, all as in effect on the date hereof and all of which are subject to change, possibly with retroactive effect. This discussion addresses holders who acquire debentures upon or subsequent to the original issuance at their original issue price and who hold the debentures and shares of our common stock as capital assets. This discussion does not address all the tax consequences that might be relevant to holders in light of their particular circumstances such as:

        If a partnership holds debentures or shares of our common stock, the tax treatment of a partner in the partnership will depend on the status of the partner and the activities of the partnership. If you are a partner in a partnership holding debentures or shares of our common stock, you are urged to consult your tax advisor.

        Prospective investors are urged to consult their own tax advisors regarding the U.S. federal, state, local and non-U.S. tax consequences of the acquisition, ownership and disposition of debentures and shares of our common stock.

U.S. holders

        The following discussion applies to you only if you are a "U.S. holder". For purposes of this discussion, a U.S. holder is a beneficial owner of debentures that is for U.S. federal income tax purposes:

28


Interest

        Payments of interest on the debentures will be taxable as ordinary income at the time the interest accrues or is received, in accordance with your method of accounting for U.S. federal income tax purposes.

        Because we are obligated to pay additional interest as liquidated damages to you under certain circumstances described under "Description of Debentures—Registration rights", the debentures may be subject to special rules under Treasury regulations that are applicable to debt instruments that provide for one or more contingent payments. Under the Treasury regulations, however, the special rules applicable to contingent payment debt instruments will not apply if, as of the issue date, the contingency is either "remote" or "incidental". We intend to take the position that, solely for these purposes, the payment of the liquidated damages is a remote or incidental contingency. Our determination that such payments are a remote or incidental contingency for these purposes is binding on you, unless you disclose in the proper manner to the IRS that you are taking a different position. You should consult your tax advisor as to the tax considerations relating to the payment of liquidated damages, in particular, in connection with the Treasury regulations relating to contingent payment debt instruments.

Conversion of debentures

        In general, you will not recognize income, gain or loss upon conversion of a debenture into shares of our common stock except with respect to (i) cash received in lieu of fractional shares and (ii) common stock received in respect of accrued but unpaid interest, as described below.

Receipt of common stock in respect of accrued interest.    The fair market value of our common stock received on conversion of debentures that is equal to accrued but unpaid interest will be taxable as ordinary income. Your tax basis in that common stock will be equal to the amount of the accrued interest included in income and your holding period for that common stock will begin on the day after the date of conversion.

Receipt of common stock other than in respect of accrued interest.    Your tax basis in our common stock received upon conversion of debentures other than in respect of accrued interest will be equal to your aggregate tax basis in the debentures less any portion of your tax basis allocable to cash received in lieu of a fractional share. Your holding period for that common stock will include the period during which you held the debentures prior to conversion. Cash received in lieu of a fractional share of common stock should be treated as a payment in exchange for the fractional share. As a result, you will generally recognize taxable gain or loss on the receipt of cash in lieu of a fractional share equal to the difference between the amount of cash received and your tax basis in the fractional share.

Deemed dividends upon conversion rate adjustments

        You might be treated as receiving a taxable deemed dividend from us if the conversion rate of the debentures is adjusted. Adjustments that have the effect of increasing your proportionate interest in our assets or earnings and profits may be treated for U.S. federal income tax purposes as dividend income to you even though you would not receive any cash related to that adjustment. You might be

29



deemed to receive a taxable dividend if the conversion rate of the debentures is adjusted as described under "Description of Debentures—Conversion rate adjustments". This will occur, for example, if there is any increase in any quarter in the quarterly dividend paid on our common stock. You also might be deemed to receive a taxable dividend if there is an increase in the conversion rate pursuant to the formula described under "Description of Debentures—Conversion rights". Your tax basis in a debenture would be increased to the extent of any such deemed dividend.

Redemption or repurchase of debentures before maturity

        The redemption or repurchase of debentures for cash will be a taxable disposition of the debentures and will be treated as described below under "Sale or disposition of debentures or shares of common stock".

Distributions on common stock acquired on conversion of debentures

        Distributions on our common stock paid out of our current or accumulated earnings and profits, as determined for U.S. federal income tax purposes, will be dividends and will be includible in your income when received. Under recently enacted legislation, dividends received by an individual taxpayer during taxable years before 2009 will be taxed at a maximum rate of 15%, provided the taxpayer held the stock for more than 60 days during the 120-day period beginning 60 days before the ex-dividend date and certain other conditions are satisfied. Dividends received by an individual taxpayer for taxable years after 2008 will be subject to tax at ordinary income rates. If you are a corporation, dividends on our common stock might qualify for a dividends received deduction.

        To the extent that the amount of any distributions on our common stock exceed our current and accumulated earnings and profits for a taxable year, it will be treated as a non-taxable return of capital to the extent of your adjusted tax basis in your shares of common stock and thereafter as capital gain.

Sale or disposition of debentures or shares of common stock

        Upon a sale or other disposition of a debenture or share of our common stock, you will recognize gain or loss equal to the difference between the amount realized and your tax basis in the debenture or share of stock, as the case may be. The amount realized on the sale or disposition of a debenture will not include payments received in respect of accrued but unpaid interest, which amount will be treated as ordinary interest income. The gain or loss upon sale or disposition of a debenture or share of our common stock will generally be capital gain or loss. Any capital gain or loss will be long-term capital gain or loss if your holding period for the debenture or share of common stock, as the case may be, is more than one year. Under recently enacted legislation, long-term capital gains of an individual taxpayer for taxable years before 2009 will be taxed at a maximum rate of 15%. For taxable years after 2008, such long-term capital gains will be taxed at a maximum rate of 20%. The deductibility of capital losses is subject to limitations.

Information reporting and backup withholding

        In general, information reporting will apply to interest on the debentures, dividends on our common stock and the proceeds of the sale or other disposition of the debentures and shares of our common stock unless you are an exempt recipient such as a corporation. Backup withholding will apply to those payments if you fail to provide your taxpayer identification number and comply with certain certification procedures or otherwise establish an exemption from backup withholding. If backup withholding applies, the relevant intermediary must withhold tax on those payments at a rate of 28% for taxable years before 2011 and a rate of 31% for subsequent taxable years. Any amounts withheld under the backup withholding rules will be allowed as a refund or credit against your U.S. federal income tax liability, provided the required information is furnished to the IRS.

30



SELLING SECURITY HOLDERS

        The debentures were originally issued on October 1, 2003 in a private placement to Goldman, Sachs & Co., J.P. Morgan Securities Inc., Banc of America Securities LLC, Citigroup Global Markets Inc., ABN AMRO Rothschild LLC, BNP Paribas Securities Corp., Credit Suisse First Boston LLC and Deutsche Bank Securities Inc. whom we refer to as the initial purchasers. The initial purchasers then resold the debentures in transactions not requiring registration under the Securities Act or applicable state securities laws to persons the initial purchasers reasonably believed to be "qualified institutional buyers", as defined in Rule 144A under the Securities Act, in compliance with Rule 144A or in other transactions exempt from registration under the Securities Act. Selling security holders may offer and sell the debentures and the underlying common stock pursuant to this prospectus.

        The following table contains information as of June 25, 2004, with respect to selling security holders and the principal amount of debentures and underlying common stock beneficially owned by each of the selling security holders that may be offered using this prospectus. The information is based on information provided by or on behalf of the selling security holders. Because the selling security holders may offer all or some of their debentures or the underlying common stock from time to time, we cannot estimate the amount of the debentures or underlying common stock that will be held by the selling security holders upon the termination of any particular offering. The column showing ownership after completion of the offering assumes that the selling security holders will sell all of the securities offered by this prospectus. The selling security holders listed in the table may have sold or transferred, in transactions exempt from the registration requirements of the Securities Act, some or all of their debentures since the date on which the information in table is presented. Information about the selling stockholders may change over time. Any change in this information will be set forth in prospectus supplements, if required. The percentage of debentures outstanding beneficially owned by each selling security holder is based on $1.2 billion aggregate principal amount of debentures outstanding. The number of shares of common stock owned prior to the offering includes shares of common stock into which the debentures are convertible. None of the selling security holders or any of their affiliates, officers, directors or principal equity holders has held any position or office and, except as indicated in the table below, none of the selling security holders has had any material relationship with us or our affiliates within the past three years.

NAME OF SELLING SECURITY HOLDER

  PRINCIPAL AMOUNT
OF DEBENTURES
BENEFICIALLY
OWNED AND
OFFERED HEREBY

  PERCENTAGE OF
OUTSTANDING
DEBENTURES
BENEFICIALLY
OWNED PRIOR TO
OFFERING

  SHARES OF COMMON
STOCK ISSUABLE
UPON CONVERSION
OF THE
DEBENTURES AND AVAILABLE FOR RESALE HEREBY (1)

  SHARES OF
COMMON STOCK
BENEFICIALLY
OWNED PRIOR TO
THE OFFERING

  PERCENTAGE OF
OUTSTANDING
COMMON STOCK
BENEFICIALLY
OWNED PRIOR TO
THE OFFERING (2)

  PRINCIPAL AMOUNT OF
DEBENTURES
BENEFICIALLY OWNED AFTER COMPLETION OF
THE OFFERING

  SHARES OF COMMON
STOCK
BENEFICIALLY
OWNED AFTER
COMPLETION OF THE OFFERING

 
HBK Master Fund L.P.   $ 17,500,000   1.45 % 678,295   711,295     * 0   33,000 (3)
DBAG London   $ 10,550,000   0.88 % 408,915   408,915     * 0   0  
Lydian Overseas Partners Master Fund   $ 20,000,000   1.67 % 775,194   775,194     * 0   0  
Laurel Ridge Capital, LP   $ 5,000,000   0.42 % 193,799   193,799     * 0   0  
AIG DKR SoundShore Strategic Holding Fund Ltd.   $ 23,000,000   1.92 % 891,473   891,473     * 0   0  
McMahan Securities Co. L.P.   $ 500,000   0.04 % 19,380   19,380     * 0   0  
Waterstone Market Neutral Offshore Fund, Ltd.   $ 5,275,000   0.44 % 204,457   204,457     * 0   0  
Waterstone Market Neutral Fund, LP   $ 1,225,000   0.10 % 47,481   47,481     * 0   0  
Marathon Global Convertible Master Fund, Ltd.   $ 15,000,000   1.25 % 581,396   581,396     * 0   0  
Akela Capital Master Fund, Ltd.   $ 12,000,000   1.00 % 465,116   465,116     * 0   0  
Nisswa Master Fund Ltd   $ 5,000,000   0.42 % 193,799   193,799     * 0   0  
Windmill Master Fund, LP   $ 13,000,000   1.08 % 503,876   503,876     * 0   0  
                                 

31


Nomura Securities Intl Inc   $ 40,000,000   3.33 % 1,550,388   7,104,778     * 0   5,554,390  
Royal Bank of Canada (4)   $ 5,000,000   0.42 % 193,799   346,231     * 0   152,432  
CNH CA Master Account, L.P.   $ 1,000,000   0.08 % 38,760   38,760     * 0   0  
Guggenheim Portfolio Company VIII, LLC   $ 2,000,000   0.17 % 77,519   77,519     * 0   0  
TD Securities (USA) Inc.   $ 36,000,000   3.00 % 1,395,349   1,395,349     * 0   0  
Fore Convertible Master Fund, Ltd.   $ 10,000,000   0.83 % 387,597   387,597     * 0   0  
Man Mac 1 Limited   $ 2,000,000   0.17 % 77,519   77,519     * 0   0  
Polygon Global Opportunities Master Fund   $ 20,000,000   1.67 % 775,194   775,194     * 0   0  
Black Diamond Convertible Offshore LDC   $ 1,661,000   0.14 % 64,380   64,380     * 0   0  
Double Black Diamond Offshore LDC   $ 4,747,000   0.40 % 183,992   183,992     * 0   0  
Black Diamond Offshore Ltd.   $ 923,000   0.08 % 35,775   35,775     * 0   0  
Worldwide Transactions Ltd.   $ 169,000   0.01 % 6,550   6,550     * 0   0  
Nicholas Applegate Capital Management Investment Grade Convertible   $ 15,000   0.00 % 581   581     * 0   0  
Amerisure Mutual Insurance Company   $ 335,000   0.03 % 12,984   12,984     * 0   0  
DB Equity Opportunities Master Portfolio Ltd   $ 4,000,000   0.33 % 155,039   155,039     * 0   0  
Pyramid Equity Strategies Fund   $ 1,000,000   0.08 % 38,760   38,760     * 0   0  
National Bank of Canada c/o Putnam Lovell NBF Securities Inc.   $ 4,000,000   0.33 % 155,039   155,039     * 0   0  
Bear Stearns & Co. Inc.   $ 16,250,000   1.35 % 629,845   629,845     * 0   0  
White River Securities L.L.C   $ 16,250,000   1.35 % 629,845   629,845     * 0   0  
S.A.C. Capital Associates, LLC   $ 15,000,000   1.25 % 581,396   592,396     * 0   11,000  
Highbridge International LLC   $ 20,000,000   1.67 % 775,194   775,194     * 0   0  
Credit Suisse First Boston LLC   $ 4,500,000   0.38 % 174,419   174,419     * 0   0  
Credit Suisse First Boston Europe Limited   $ 15,175,000   1.26 % 588,178   588,178     * 0   0  
R2 Investments, LDC   $ 1,250,000   0.10 % 48,450   48,450     * 0   0  
Lyxor/AM Investment Fund Ltd.   $ 1,960,000   0.16 % 75,969   75,969     * 0   0  
AM Master Fund I LP   $ 10,640,000   0.89 % 412,403   412,403     * 0   0  
Clinton Riverside Convertible Portfolio Limited   $ 19,320,000   1.61 % 748,837   748,837     * 0   0  
Clinton Multistrategy Master Fund, Ltd.   $ 7,330,000   0.61 % 284,109   284,109     * 0   0  
CQS Convertible & Quantitative Strategies Master Fund Limited   $ 10,500,000   0.88 % 406,977   406,977     * 0   0  
                                 

32


AmerUS Life Insurance Company   $ 4,600,000   0.38 % 178,295   178,295     * 0   0  
American Investors Life Insurance Company   $ 400,000   0.03 % 15,504   15,504     * 0   0  
Bankers Life Insurance Company of New York   $ 100,000   0.01 % 3,876   3,876     * 0   0  
Dodeca Fund, L.P.   $ 1,925,000   0.16 % 74,612   74,612     * 0   0  
Indianapolis Life Insurance Company   $ 22,400,000   1.87 % 868,217   868,217     * 0   0  
Inflective Convertible Opportunity Fund I, L.P.   $ 75,000   0.01 % 2,907   2,907     * 0   0  
The Drake Offshore Master Fund, Ltd.   $ 11,500,000   0.96 % 445,737   445,737     * 0   0  
Wachovia Securities International Ltd.   $ 15,000,000   1.25 % 581,396   581,396     * 0   0  
Canadian Imperial Holdings, Inc.   $ 15,000,000   1.25 % 581,396   581,396     * 0   0  
Goldman Sachs International   $ 13,925,000   1.16 % 539,729   630,016     * 0   90,287 (5)
Goldman Sachs & Co.   $ 69,965,000   5.83 % 2,711,822   8,977,323     * 0   6,265,501 (6)
Commercial Union Life Fund   $ 1,000,000   0.08 % 38,760   38,760     * 0   0  
CGNU Life Fund   $ 800,000   0.07 % 31,008   31,008     * 0   0  
Norwich Union Life & Pensions   $ 1,200,000   0.10 % 46,512   46,512     * 0   0  
FrontPoint Convertible Arbitrage Fund, L.P.   $ 5,000,000   0.41 % 193,799   193,799     * 0   0  
Credit Lyonnais Securities (USA) Inc.   $ 17,000,000   1.42 % 658,915   658,915     * 0   0  
KBC Financial Products USA Inc.   $ 6,470,000   0.54 % 250,775   250,775     * 0   0  
Citigroup Global Markets Inc.   $ 2,500,000   0.21 % 96,899   96,899     * 0   0  
Xavex Convertible Arbitrage 5 Fund   $ 2,000,000   0.17 % 77,519   77,519     * 0   0  
Bank Austria Cayman Islands, Ltd.   $ 2,000,000   0.17 % 77,519   77,519     * 0   0  
RCG Latitude Master Fund, Ltd.   $ 10,000,000   0.83 % 387,597   387,597     * 0   0  
RCG Multi Strategy Master Fund, Ltd.   $ 5,000,000   0.42 % 193,799   193,799     * 0   0  
Ramius Master Fund, Ltd.   $ 10,000,000   0.83 % 387,597   387,597     * 0   0  
Guggenheim Portfolio Company XV, LLC   $ 1,500,000   0.13 % 58,140   58,140     * 0   0  
JPMorgan Securities Inc.   $ 13,700,000   1.14 % 531,008   762,961     * 0   231,953  
Swiss Re Financial Products Corporation   $ 27,500,000   2.29 % 1,065,892   1,065,892     * 0   0  
Wachovia Capital Markets LLC   $ 19,000,000   1.58 % 736,434   736,434     * 0   0  
Wachovia Bank National Association   $ 20,300,000   1.69 % 786,822   786,822     * 0   0  
Citadel Equity Fund Ltd.   $ 8,850,000   0.74 % 343,023   343,023     * 0   0  
Citadel Jackson Investment Fund Ltd.   $ 1,150,000   0.10 % 44,574   44,574     * 0   0  
Advisory Convertible Arbitrage Fund (I) L.P.   $ 1,000,000   0.08 % 38,760   38,760     * 0   0  
                                 

33


Deephaven Domestic Convertible Trading Ltd.   $ 52,152,000   4.35 % 2,021,396   2,021,396     * 0   0  
Sphinx Convertible Arbitrage Fund SPC   $ 848,000   0.07 % 32,868   32,868     * 0   0  
Victus Capital, LP   $ 7,000,000   0.58 % 271,318   271,318     * 0   0  
Associated Electric & Gas Insurance Services Limited   $ 800,000   0.07 % 31,008   31,008     * 0   0  
Tribeca Investments L.T.D.   $ 28,000,000   2.33 % 1,085,272   1,085,272     * 0   0  
Quest Global Convertible Master Fund Ltd   $ 3,000,000   0.25 % 116,279   116,279     * 0   0  
Lighthouse Multi-Strategy Master Fund Ltd.   $ 500,000   0.04 % 19,380   19,380     * 0   0  
State of Florida Division of Treasury   $ 2,300,000   0.19 % 89,147   89,147   *   0   0  
Davidson Kempner International Limited     7,833,000   0.65 % 303,604   303,604   *   0   0  
Davidson Kempner Institutional Limited     5,975,000   0.50 % 231,589   231,589   *   0   0  
Davidson Kempner Partners     3,382,500   0.28 % 131,105   131,105   *   0   0  
Serena Limited     309,500   .03 % 11,996   11,996   *   0   0  
UBS AG London     60,000,000   5.00 % 2,325,582   2,325,582   *   0   0  
Hamilton Multi-Strategy Master Fund, LP     5,877,000   0.49 % 227,791   227,791   *   0   0  
Manmac 2 Limited     4,123,000   0.34 % 159,806   159,806   *   0   0  
AG Offshore Convertibles, LTD     15,750,000   1.31 % 610,465   610,465   *   0   0  
AG Domestic Convertibles, L.P.     6,750,000   0.56 % 261,628   261,628   *   0   0  
UBS Securities LLC     19,605,000   1.63 % 759,884   759,884   *   0   0  
UBS O'Connor LLC f/b/o UBS Global Convertible Arbitrage Master Ltd     20,000,000   1.66 % 775,194   775,194   *   0   0  
Lehman Brothers Inc.     41,300,000   3.44 % 1,600,776   1,600,776   *   0   0  
Any other holder of debentures or future transferees, pledge, donee or successor (7)(8)                                

*
Less than 1% of total outstanding common stock.

(1)
Assumes conversion of all of the holder's debentures at a maximum conversion rate of 38.7597 shares per $1,000 principal amount. Fractions of a share are not included for the purposes of this calculation. The debentures were designed so that holders may at any time prior to maturity convert them into shares of our common stock at a conversion rate that will vary until September 15, 2008, depending on the applicable stock price, as described under "Description of the Debentures—Conversion rights". In addition, the conversion price will also be subject to adjustment as described under "Description of the Debentures—Conversion rate adjustments". As a result, the amount of common stock issuable upon conversion of the debentures is likely to increase or decrease in the future.

(2)
Calculated based on Rule 13d-3(d)(1)(i) of the Exchange Act, using 1,945,132,685 shares of common stock outstanding as of June 25, 2004.

(3)
Included in this amount is holder's option to purchase 20,500 shares of the Company's common stock.

(4)
Holder has various lending relationships with the Company and may be counterparty to such relationships.

(5)
Included in this amount is holder's option to purchase 62,500 shares of the Company's common stock.

(6)
Included in this amount is holder's option to purchase 190,200 shares of the Company's common stock.

(7)
Information about other selling security holders will be set forth in prospectus supplements, if required.

(8)
Assumes that any other holders of debentures, or any future transferees, pledgees, donees or successors of or from any other such holders of debentures, do not beneficially own any common stock other than the common stock issuable upon conversion of the debentures at the initial conversion rate.

34



PLAN OF DISTRIBUTION

        We will not receive any of the proceeds of the sale of the debentures and the underlying common stock offered by this prospectus. The debentures and the underlying common stock may be sold from time to time to purchasers:

        The selling security holders and any such broker-dealers or agents who participate in the distribution of the debentures and the underlying common stock may be deemed to be "underwriters". As a result, any profits on the sale of the debentures and underlying common stock by selling security holders and any discounts, commissions or concessions received by any such broker-dealers or agents might be deemed to be underwriting discounts and commissions under the Securities Act. If the selling security holders were to be deemed underwriters, the selling security holders may be subject to certain statutory liabilities of, including, but not limited to, Sections 11, 12 and 17 of the Securities Act and Rule 10b-5 under the Exchange Act.

        If the debentures and underlying common stock are sold through underwriters or broker-dealers, the selling security holders will be responsible for underwriting discounts or commissions or agent's commissions.

        The debentures and underlying common stock may be sold in one or more transactions at:

        These sales may be effected in transactions:

        These transactions may include block transactions or crosses. Crosses are transactions in which the same broker acts as an agent on both sides of the trade.

        In connection with sales of the debentures and underlying common stock or otherwise, the selling security holders may enter into hedging transactions with broker-dealers. These broker-dealers may in turn engage in short sales of the debentures and underlying common stock in the course of hedging their positions. The selling security holders may also sell the debentures and underlying common stock short and deliver debentures and underlying common stock to close out short positions, or loan or pledge debentures and underlying common stock to broker-dealers that in turn may sell the debentures and underlying common stock.

        To our knowledge, there are currently no plans, arrangements or understandings between any selling security holder and any underwriter, broker-dealer or agent regarding the sale of the debentures and the underlying common stock by the selling security holders. There is no assurance that any selling security holders will sell any or all of the debentures and the underlying common stock offered by them pursuant to this prospectus. In addition, we cannot assure you that any such selling security holder will

35



not transfer, devise or gift the debentures and the underlying common stock by other means not described in this prospectus.

        Our common stock trades on the New York Stock Exchange under the symbol "BMY". We do not intend to apply for listing of the debentures on any securities exchange or on any automated quotation system. Accordingly, no assurance can be given as to the development of liquidity or any trading market for the debentures. See "Risk Factors—Risks Related to the Debentures".

        In addition, any securities covered by this prospectus which qualify for sale pursuant to Rule 144, Rule 144A or any other available exemption from registration under the Securities Act may be sold under Rule 144, Rule 144A or any of the other available exemptions rather than pursuant to this prospectus.

        The selling security holders and any other person participating in such distribution will be subject to the Exchange Act. The Exchange Act rules include, without limitation, Regulation M, which may limit the timing of purchases and sales of any of the debentures and the underlying common stock by the selling security holders and any other such person. In addition, Regulation M of the Exchange Act may restrict the ability of any person engaged in the distribution of the debentures and the underlying common stock to engage in market-making activities with respect to the particular debentures and the underlying common stock being distributed for a period of up to five business days prior to the commencement of such distribution. This may affect the marketability of the debentures and the underlying common stock and the ability of any person or entity to engage in market-making activities with respect to the debentures and the underlying common stock.

        Pursuant to the registration rights agreement incorporated by reference into the registration statement of which this prospectus is a part, we and the selling security holders will be indemnified by the other against certain liabilities, including certain liabilities under the Securities Act or will be entitled to contribution in connection with these liabilities.

        We have agreed to bear all fees and expenses incurred in connection with the performance of our obligations with respect to the shelf registration, the registration procedures and sales in connection with an underwritten offering pursuant to Section 6 of the Registration Rights Agreement. Each selling security holder shall pay discounts and commissions and transfer taxes, if any, relating to the sale or disposition of its securities pursuant to this registration statement.


LEGAL MATTERS

        Cravath, Swaine & Moore LLP, New York, New York, will pass upon the legality of the debentures for us.


INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

        The financial statements incorporated in this Prospectus by reference to the Annual Report on Form 10-K/A for the year ended December 31, 2003 have been so incorporated in reliance on the report (which contains explanatory paragraphs relating to the restatement of previously issued financial statements and a change in accounting principle relating to the accounting for business combinations, the accounting treatment for goodwill and the impairment of long-lived assets) of PricewaterhouseCoopers LLP, an independent registered public accounting firm, given on the authority of said firm as experts in auditing and accounting.

        With respect to the unaudited financial information of Bristol-Myers Squibb Company for the three-month periods ended March 31, 2004 and 2003, incorporated by reference in this Prospectus, PricewaterhouseCoopers LLP reported that they have applied limited procedures in accordance with professional standards for a review of such information. However, their separate report dated May 4, 2004 incorporated by reference herein, states that they did not audit and they do not express an opinion on that unaudited financial information. Accordingly, the degree of reliance on their report on such information should be restricted in light of the limited nature of the review procedures applied. PricewaterhouseCoopers LLP is not subject to the liability provisions of Section 11 of the Securities Act of 1933 for their report on the unaudited financial information because that report is not a "report" or a "part" of the registration statement prepared or certified by PricewaterhouseCoopers LLP within the meaning of Sections 7 and 11 of the Act.

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NOTE REGARDING FORWARD-LOOKING STATEMENTS

        This prospectus and the documents incorporated by reference in this prospectus and other written and oral statements Bristol-Myers Squibb makes from time to time may contain certain "forward-looking" statements within the meaning of Section 27A of the Securities Act and Section 21E of the Securities Exchange Act of 1934, as amended (the Exchange Act). You can identify these forward-looking statements by the fact that they use words such as "should", "expect", "target", "anticipate", "estimate", "may", "will", "project", "guidance", "intend", "plan", "believe" and other words and terms of similar meaning and expression in connection with any discussion of future operating or financial performance. One can also identify forward-looking statements by the fact that they do not relate strictly to historical or current facts. Such forward-looking statements are based on current expectations and involve inherent risks and uncertainties, including factors that could delay, divert or change any of them, and could cause actual outcomes to differ materially from current expectations. These statements are likely to relate to, among other things, Bristol-Myers Squibb's goals, plans and projections regarding its financial position, results of operations, market position, product development, product approvals, sales efforts, expenses, performance or results of current and anticipated products and the outcome of contingencies such as legal proceedings, and financial results which are based on current expectations that involve inherent risks and uncertainties, including factors that could delay, divert or change any of them in the next several years.

        Although it is not possible to predict or identify all factors, they may include but are not limited to the following:

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        Although Bristol-Myers Squibb believes it has been prudent in its plans and assumptions, no assurance can be given that any goal or plan set forth in forward-looking statements can be achieved and readers are cautioned not to place undue reliance on such statements, which speak only as of the date made. Bristol-Myers Squibb undertakes no obligation to release publicly any revisions to forward-looking statements as a result of new information, future events or otherwise.

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WHERE YOU CAN FIND MORE INFORMATION

        We file annual, quarterly and special reports, proxy statements and other information with the SEC. Our SEC filings are available over the Internet at the SEC's website at http://www.sec.gov. You may also read and copy any document we file with the SEC at its public reference facilities:

Public Reference Room
450 Fifth Street, N.W.
Room 1024
Washington, D.C. 20549

        You may also obtain copies of the documents at prescribed rates by writing to the Public Reference Section of the SEC, 450 Fifth Street, N.W., Room 1024, Washington, D.C. 20549. Please call 1-800-SEC-0330 for further information on the operations of the public reference facilities and copying charges.


CERTAIN DOCUMENTS INCORPORATED BY REFERENCE

        In this document, we "incorporate by reference" the information we file with the SEC, which means that we can disclose important information to you by referring to that information. The information incorporated by reference is considered to be a part of this prospectus, and later information filed with the SEC will update and supersede this information. Notwithstanding this statement, however, you may rely on information that has been filed at the time you made your investment decision. We incorporate by reference the documents listed below and any future filings made with the SEC under Section 13(a), 13(c), 14 or 15(d) of the Exchange Act after the date of this prospectus and until this offering is completed:

        You may request a copy of these filings at no cost, by writing or telephoning us at:

Bristol-Myers Squibb Company
345 Park Avenue
New York, New York 10154
Attention: Secretary
Telephone: 212-546-4000

        If at any time during the two-year period following the later of the date of original issue of the debentures and the date of issue with respect to additional debentures pursuant to the initial purchasers' option, if exercised, we are not subject to the information requirements of Section 13 or 15(d) of the Exchange Act, we will furnish to holders of debentures and prospective purchasers thereof the information required to be delivered pursuant to Rule 144A(d)(4) under the Securities Act in order to permit compliance with Rule 144A in connection with resales of such debentures.

        You should rely only upon the information provided in this document or incorporated in this document by reference. We have not authorized anyone to provide you with different information. You should not assume that the information in this document, including any information incorporated by reference, is accurate as of any date other than the date indicated on the front cover.

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$1,200,000,000

Bristol-Myers Squibb Company

Floating Rate Convertible Senior Debentures Due 2023


GRAPHIC




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TABLE OF CONTENTS
PROSPECTUS SUMMARY
RISK FACTORS
THE COMPANY
USE OF PROCEEDS
DESCRIPTION OF DEBENTURES
DESCRIPTION OF COMMON STOCK
CERTAIN U.S. FEDERAL INCOME TAX CONSIDERATIONS
SELLING SECURITY HOLDERS
PLAN OF DISTRIBUTION
LEGAL MATTERS
INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
NOTE REGARDING FORWARD-LOOKING STATEMENTS
WHERE YOU CAN FIND MORE INFORMATION
CERTAIN DOCUMENTS INCORPORATED BY REFERENCE