UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
SCHEDULE 13G
Under the Securities Exchange Act of 1934
(Amendment No. 1)*
REGENXBIO Inc. (Name of Issuer)
Common Stock
(Title of Class of Securities)
75901B107 (CUSIP Number)
December 31, 2016
(Date of Event which Requires Filing of this Statement)
Check the appropriate box to designate the rule pursuant
to which this Schedule is filed:
? Rule 13d-1(b)
? Rule 13d-1(c)
? Rule 13d-1(d)
* The remainder of this cover page shall be filled out for
a reporting person's initial filing on this form with
respect to the subject class of securities, and for any
subsequent amendment containing information which would
alter disclosures provided in a prior
cover page.
The information required on the remainder of this cover
page shall not be deemed to be "filed" for the purpose
of Section 18 of the Securities Exchange Act of 1934
("Act") or otherwise subject to the liabilities of that
section of the Act but shall be subject to
all other provisions of the Act (however, see the Notes).
CUSIP No. 75901B107
13G
Page 2 of 6 Pages
1.
NAMES OF REPORTING PERSONS
Brookside Capital Partners Fund, L.P.
2.
CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
(see instructions)
(a) ?
(b) ?
3.
SEC USE ONLY
4.
CITIZENSHIP OR PLACE OF ORGANIZATION
Delaware
NUMBER OF
SHARES
BENEFICIALLY
OWNED BY
EACH
REPORTING
PERSON WITH
5.
SOLE VOTING POWER
1,759,961
6.
SHARED VOTING POWER
0
7.
SOLE DISPOSITIVE POWER
1,759,961
8.
SHARED DISPOSITIVE POWER
0
9.
AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
1,759,961
10.
CHECK IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES
(see instructions) ?
11.
PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)
6.65%
12.
TYPE OF REPORTING PERSON (see instructions)
PN
CUSIP No. 75901B107
13G
Page 3 of 6 Pages
1.
NAMES OF REPORTING PERSONS
Brookside Capital Trading Fund, L.P.
2.
CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
(see instructions)
(a) ?
(b) ?
3.
SEC USE ONLY
4.
CITIZENSHIP OR PLACE OF ORGANIZATION
Delaware
NUMBER OF
SHARES
BENEFICIALLY
OWNED BY
EACH
REPORTING
PERSON WITH
5.
SOLE VOTING POWER
734,398
6.
SHARED VOTING POWER
0
7.
SOLE DISPOSITIVE POWER
734,398
8.
SHARED DISPOSITIVE POWER
0
9.
AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
734,398
10.
CHECK IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES
(see instructions) ?
11.
PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)
2.77%
12.
TYPE OF REPORTING PERSON (see instructions)
PN
CUSIP No. 75901B107
13G
Page 4 of 6 Pages
Item 1.
(a)
Name of Issuer
The name of the issuer to which this filing on Schedule
13G relates is REGENXBIO Inc. (the "Company")
(b)
Address of Issuer's Principal Executive Offices
The principal executive offices of the Company are located at
9712 Medical Center Drive, Suite 100, Rockville, MD
20850.
Item 2.
(a)
Name of Person Filing
This Statement is being filed on behalf the following
(collectively, the "Reporting Persons"): (1) Brookside Capital
Partners Fund, L.P., a Delaware limited partnership
("Partners Fund"), whose sole general partner is
Brookside Capital Investors, L.P., a Delaware limited
partnership ("Brookside Investors"), whose sole general
partner is Bain Capital Public Equity Management, LLC, a
Delaware limited liability company ("BCPE Management");
and (2) Brookside Capital Trading Fund, L.P., a Delaware
limited partnership ("Trading Fund"), whose sole general
partner is Brookside Capital Investors II, L.P., a
Delaware limited partnership ("Brookside Investors II"),
whose sole general partner is BCPE Management.
The Reporting Persons have entered into a Joint Filing
Agreement, dated February 14, 2017, a copy of which is filed
with this Schedule 13G as Exhibit A, pursuant to which the
Reporting Persons have agreed to file this statement jointly
in accordance with the provisions of Rule 13d-1(k)(1)
under the Securities Exchange Act of 1934.
(b)
Address of the Principal Office or, if none, residence
The principal business address of each of the Partners Fund,
the Trading Fund, Brookside Investors, Brookside Investors II,
and BCPE Management is c/o Bain Capital Public Equity, LP,
200 Clarendon Street, Boston, MA 02116.
(c)
Citizenship
Each of the Partners Fund, the Trading Fund, Brookside Investors,
Brookside Investors II and BCPE Management is
organized under the laws of the State of Delaware.
(d)
Title of Class of Securities
The class of equity securities of the Company to which this filing
on Schedule 13G relates is Common Stock
("Common Stock").
(e)
CUSIP Number
The CUSIP number of the Company's Common Stock is 75901B107.
Item 3. If this statement is filed pursuant to 240.13d-1(b) or
240.13d-2(b) or (c), check whether the person filing is a:
(a)
?
Broker or dealer registered under section 15 of the Act (15 U.S.C. 78o).
(b)
?
Bank as defined in section 3(a)(6) of the Act (15 U.S.C. 78c).
(c)
?
Insurance company as defined in section 3(a)(19) of the Act (15 U.S.C. 78c).
(d)
?
Investment company registered under section 8 of the Investment
Company Act of 1940 (15 U.S.C. 80a-8).
(e)
?
An investment adviser in accordance with 240.13d-1(b)(1)(ii)(E);
(f)
?
An employee benefit plan or endowment fund in accordance
with 240.13d-1(b)(1)(ii)(F);
(g)
?
A parent holding company or control person in
accordance with 240.13d-1(b)(1)(ii)(G);
(h)
?
A savings associations as defined in Section 3(b) of the Federal
Deposit Insurance Act (12 U.S.C. 1813);
(i)
?
A church plan that is excluded from the definition of an
investment company under section 3(c)(14) of the
Investment Company Act of 1940 (15 U.S.C. 80a-3);
(j)
?
Group, in accordance with 240.13d-1(b)(1)(ii)(J).
[x] If this statement is filed pursuant to 240.13d-1(c), check this box.
Item 4. Ownership.
Provide the following information regarding the aggregate number
and percentage of the class of securities of the issuer
identified in Item 1.
(a)
Amount beneficially owned: 2,494,359
(b)
Percent of class: 9.42% based upon 26,475,379 shares of
Common Stock outstanding.
(c)
Number of shares as to which the person has: 2,494,359.
(i)
Sole power to vote or to direct the vote: 2,494,359.
(ii)
Shared power to vote or to direct the vote: 0.
(iii)
Sole power to dispose or to direct the disposition of: 2,494,359.
(iv)
Shared power to dispose or to direct the disposition of: 0.
Item 5. Ownership of Five Percent or Less of a Class.
Not applicable.
Item 6. Ownership of More than Five Percent on
Behalf of Another Person.
Not applicable.
Item 7. Identification and Classification of the
Subsidiary Which Acquired the Security Being Reported on By the Parent
Holding Company.
Not applicable.
Item 8. Identification and Classification of
Members of the Group.
Not applicable.
Item 9. Notice of Dissolution of Group.
Not applicable.
Item 10. Certification.
By signing below I certify that, to the best of my knowledge and
belief, the securities referred to above were not acquired and are
not held for the purpose of or with the effect of changing or
influencing the control of the issuer of the securities and were
not acquired and are not held in connection with or as a
participant in any transaction having that purpose or effect.
CUSIP No. 75901B107
13G
Page 6 of 6 Pages
After reasonable inquiry and to the best of my knowledge and
belief, I certify that the information set forth in this statement
is true, complete and correct.
Dated: February 14, 2017
BROOKSIDE CAPITAL PARTNERS FUND, L.P.
By: Brookside Capital Investors, L.P.,
its general partner
By: Bain Capital Public Equity Management, LLC,
its general partner
By:
Name:
Title:
BROOKSIDE CAPITAL TRADING FUND, L.P.
By: Brookside Capital Investors II, L.P.,
its general partner
By: Bain Capital Public Equity Management, LLC,
its general partner
By:
Name:
Title:
Exhibit A
AGREEMENT REGARDING THE JOINT FILING OF
SCHEDULE 13G
The undersigned hereby agree as follows:
(i) The Statement on Schedule 13G, and any amendments
thereto, to which this Agreement is annexed as Exhibit A
is and will be filed on behalf of each of them in
accordance with the provisions of Rule 13d-1(k)(1) under the
Securities Exchange Act of 1934, as amended; and
(ii) Each of them is responsible for the timely filing
of such Schedule 13G and any amendments thereto, and for the
completeness and accuracy of the information concerning
such person contained therein; but none of them is
responsible for the completeness or accuracy of the
information concerning the other persons making the filing,
unless such person knows or has reason to believe that
such information is inaccurate.
Dated: February 14, 2017
BROOKSIDE CAPITAL PARTNERS FUND, L.P.
By: Brookside Capital Investors, L.P.,
its general partner
By: Bain Capital Public Equity Management, LLC,
its general partner
By:
Name:
Title:
BROOKSIDE CAPITAL TRADING FUND, L.P.
By: Brookside Capital Investors II, L.P.,
its general partner
By: Bain Capital Public Equity Management, LLC,
its general partner
The percentage of Common Stock reported owned by the
Reporting Persons is based upon 26,475,379 shares of Common Stock
outstanding as reported in the Issuer's Quarterly Report on
Form 10-Q filed November 9, 2016. The percentage of Common Stock
reported owned by the Reporting Persons is based upon 26,475,379
shares of Common Stock
outstanding as reported in the Issuer's Quarterly Report on Form
0-Q filed November 9, 2016.
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