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|
|
|
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1
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NAME OF REPORTING PERSONS
Rock Springs Capital Master Fund LP
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2
|
CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
(a) o
(b) o
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3
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SEC USE ONLY
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4
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CITIZENSHIP OR PLACE OF ORGANIZATION
Cayman Islands
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NUMBER OF
SHARES
BENEFICIALLY
OWNED BY
EACH
REPORTING
PERSON
WITH
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5
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SOLE VOTING POWER
0
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6
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SHARED VOTING POWER
5,697,000
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7
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SOLE DISPOSITIVE POWER
0
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8
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SHARED DISPOSITIVE POWER
5,697,000
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9
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AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
5,697,000
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10
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CHECK IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES
|
o
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11
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PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)
5.32%
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12
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TYPE OF REPORTING PERSON
PN
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CUSIP No. 00461U105
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Schedule 13G
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Page 5
of 9 Pages
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Item 1. | | (a) Name of Issuer |
Aclaris Therapeutics, Inc. (the “Issuer”)
| | (b) Address of Issuer’s Principal
Executive Offices |
701
Lee Road, Suite 103
Wayne,
PA 19087
Item 2. | | (a) Name of Person Filing |
This
Statement is filed on behalf of each of the following persons (collectively, the “Reporting Persons”):
i.
Rock Springs Capital Management LP (“RSCM”);
ii.
Rock Springs Capital LLC (“RSC”); and
iii.
Rock Springs Capital Master Fund LP (“Master Fund”).
This
Statement relates to Shares (as defined herein) held directly by the Master Fund, which is a Cayman Island exempted limited
partnership, and Four Pines Master Fund LP (“Four Pines”), which is a Cayman Islands exempted limited
partnership, and indirectly held by RSCM, a Delaware limited partnership, and RSC, a Delaware limited liability company. RSCM
serves as the investment manager to each of the Master Fund and Four Pines. RSC is the general partner of RSCM.
| | (b) Address
of Principal Business Office, or, if none, Residence |
Rock
Springs Capital Management LP and Rock Springs Capital LLC
650 South Exeter, Suite 1070
Baltimore, MD 21202
Rock
Springs Capital Master Fund
c/o
Walkers Corporate Limited
190
Elgin Avenue
George
Town, Grand Cayman, KY1-9008, Cayman Islands
Rock
Springs Capital Management LP - Delaware
Rock
Springs Capital LLC - Delaware
Rock
Springs Capital Master Fund LP - Cayman Islands
| | (d) Title of Class of Securities |
Common Stock, $0.00001 par value (the “Shares”)
00461U105
CUSIP No. 00461U105
|
Schedule 13G
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Page 6
of 9 Pages
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(a) |
¨ |
Broker or dealer registered under section 15 of the Act (15 U.S.C. 78o); |
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(b) |
¨ |
Bank as defined in section 3(a)(6) of the Act (15 U.S.C. 78c); |
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(c) |
¨ |
Insurance company as defined in section 3(a)(19) of the Act (15 U.S.C. 78c); |
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(d) |
¨ |
Investment company registered under section 8 of the Investment Company Act of 1940 (15 U.S.C. 80a-8); |
|
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(e) |
o |
An investment adviser in accordance with §240.13d-1(b)(1)(ii)(E); |
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(f) |
¨ |
An employee benefit plan or endowment fund in accordance with §240.13d-1(b)(1)(ii)(F); |
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(g) |
o |
A parent holding company or control person in accordance with §240.13d-1(b)(1)(ii)(G); |
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(h) |
¨ |
A savings associations as defined in Section 3(b) of the Federal Deposit Insurance Act (12 U.S.C. 1813); |
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(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); |
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(j) |
¨ |
A non-U.S. institution in accordance with §240.13d-1(b)(1)(ii)(J); |
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(k) |
¨ |
A group, in accordance with §240.13d-1(b)(1)(ii)(K). If filing as a non-U.S. institution in accordance with §240.13d-1(b)(1)(ii)(J),
please specify the type of institution: |
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Provide
the following information regarding the aggregate number and percentage of the class of securities of the issuer identified
in Item 1.
As of
November 18, 2024, each of RSCM and RSC may be deemed to be the beneficial owners of 6,761,861 Shares, which amount includes
5,697,000 Shares directly beneficially owned by the Master Fund, and 1,064,861 Shares directly beneficially owned by Four Pines. The
percent of class is determined by dividing the number of Shares beneficially owned by the Reporting Persons by 106,986,497 as
reported on the Issuer’s Form 8-K filed on November 18, 2024.