CUSIP
No. 002120103
|
13G/A
|
Page
2 of 15 Pages
|
1
|
NAME
OF REPORTING PERSON
S.S.
OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON (ENTITIES ONLY)
Viking Global Investors LP
|
2
|
CHECK
THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
(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
0
|
6
|
SHARED
VOTING POWER
816,728*
|
7
|
SOLE
DISPOSITIVE POWER
0
|
8
|
SHARED
DISPOSITIVE POWER
816,728*
|
9
|
AGGREGATE
AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
816,728
|
10
|
CHECK
BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES* ☐
|
11
|
PERCENT
OF CLASS REPRESENTED BY AMOUNT IN ROW 9
9.4%
|
12
|
TYPE
OF REPORTING PERSON
PN
|
|
|
|
|
|
|
_________________________
*See Item 4
CUSIP
No. 002120103
|
13G/A
|
Page
3 of 15 Pages
|
1
|
NAME
OF REPORTING PERSON
S.S.
OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON (ENTITIES ONLY)
Viking Global Opportunities GP LLC
|
2
|
CHECK
THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
(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
0
|
6
|
SHARED
VOTING POWER
816,728*
|
7
|
SOLE
DISPOSITIVE POWER
0
|
8
|
SHARED
DISPOSITIVE POWER
816,728*
|
9
|
AGGREGATE
AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
816,728*
|
10
|
CHECK
BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES* ☐
|
11
|
PERCENT
OF CLASS REPRESENTED BY AMOUNT IN ROW 9
9.4%*
|
12
|
TYPE
OF REPORTING PERSON
OO
|
|
|
|
|
|
|
______________________
*
See Item 4
CUSIP
No. 002120103
|
13G/A
|
Page
4 of 15 Pages
|
1
|
NAME
OF REPORTING PERSON
I.R.S.
IDENTIFICATION NO. OF ABOVE PERSON (ENTITIES ONLY)
Viking Global Opportunities Portfolio GP LLC
|
2
|
CHECK
THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
(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
0
|
6
|
SHARED
VOTING POWER
816,728*
|
7
|
SOLE
DISPOSITIVE POWER
0
|
8
|
SHARED
DISPOSITIVE POWER
816,728*
|
9
|
AGGREGATE
AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
816,728*
|
10
|
CHECK
BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES* ☐
|
11
|
PERCENT
OF CLASS REPRESENTED BY AMOUNT IN ROW 9
9.4%*
|
12
|
TYPE
OF REPORTING PERSON*
OO
|
|
|
|
|
|
|
______________________
*
See Item 4
CUSIP
No. 002120103
|
13G/A
|
Page
5 of 15 Pages
|
1
|
NAME
OF REPORTING PERSON
S.S.
OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON (ENTITIES ONLY)
Viking Global Opportunities Illiquid Investments Sub-Master LP
|
2
|
CHECK
THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
(a)
☐
(b) ☒
|
3
|
SEC
USE ONLY
|
4
|
CITIZENSHIP
OR PLACE OF ORGANIZATION
Cayman Islands
|
NUMBER
OF
SHARES
BENEFICIALLY
OWNED
BY
EACH
REPORTING
PERSON
WITH
|
5
|
SOLE
VOTING POWER
0
|
6
|
SHARED
VOTING POWER
816,728*
|
7
|
SOLE
DISPOSITIVE POWER
0
|
8
|
SHARED
DISPOSITIVE POWER
816,728*
|
9
|
AGGREGATE
AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
816,728*
|
10
|
CHECK
BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES* ☐
|
11
|
PERCENT
OF CLASS REPRESENTED BY AMOUNT IN ROW 9
9.4%*
|
12
|
TYPE
OF REPORTING PERSON
PN
|
|
|
|
|
|
|
____________________
*
See Item 4
CUSIP
No. 002120103
|
13G/A
|
Page
6 of 15 Pages
|
1
|
NAME
OF REPORTING PERSON
S.S.
OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON (ENTITIES ONLY)
O. Andreas Halvorsen
|
2
|
CHECK
THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
(a)
☐
(b) ☒
|
3
|
SEC
USE ONLY
|
4
|
CITIZENSHIP
OR PLACE OF ORGANIZATION
Norway
|
NUMBER
OF
SHARES
BENEFICIALLY
OWNED
BY
EACH
REPORTING
PERSON
WITH
|
5
|
SOLE
VOTING POWER
0
|
6
|
SHARED
VOTING POWER
816,728*
|
7
|
SOLE
DISPOSITIVE POWER
0
|
8
|
SHARED
DISPOSITIVE POWER
816,728*
|
9
|
AGGREGATE
AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
816,728*
|
10
|
CHECK
BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES* ☐
|
11
|
PERCENT
OF CLASS REPRESENTED BY AMOUNT IN ROW 9
9.4%*
|
12
|
TYPE
OF REPORTING PERSON
IN
|
|
|
|
|
|
|
____________________
*
See Item 4
CUSIP
No. 002120103
|
13G/A
|
Page
7 of 15 Pages
|
1
|
NAME
OF REPORTING PERSON
I.R.S.
IDENTIFICATION NO. OF ABOVE PERSON (ENTITIES ONLY)
David C. Ott
|
2
|
CHECK
THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
(a)
☐
(b) ☒
|
3
|
SEC
USE ONLY
|
4
|
CITIZENSHIP
OR PLACE OF ORGANIZATION
United States
|
NUMBER OF
SHARES
BENEFICIALLY
OWNED
BY
EACH
REPORTING
PERSON
WITH
|
5
|
SOLE
VOTING POWER
0
|
6
|
SHARED
VOTING POWER
816,728*
|
7
|
SOLE
DISPOSITIVE POWER
0
|
8
|
SHARED
DISPOSITIVE POWER
816,728*
|
9
|
AGGREGATE
AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
816,728*
|
10
|
CHECK
BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES* ☐
|
11
|
PERCENT
OF CLASS REPRESENTED BY AMOUNT IN ROW 9
9.4%*
|
12
|
TYPE
OF REPORTING PERSON*
IN
|
|
|
|
|
|
|
____________________
*
See Item 4
CUSIP
No. 002120103
|
13G/A
|
Page
8 of 15 Pages
|
1
|
NAME
OF REPORTING PERSON
I.R.S.
IDENTIFICATION NO. OF ABOVE PERSON (ENTITIES ONLY)
Rose S. Shabet
|
2
|
CHECK
THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
(a)
☐
(b) ☒
|
3
|
SEC
USE ONLY
|
4
|
CITIZENSHIP
OR PLACE OF ORGANIZATION
United States
|
NUMBER OF
SHARES
BENEFICIALLY
OWNED
BY
EACH
REPORTING
PERSON
WITH
|
5
|
SOLE
VOTING POWER
0
|
6
|
SHARED
VOTING POWER
816,728*
|
7
|
SOLE
DISPOSITIVE POWER
0
|
8
|
SHARED
DISPOSITIVE POWER
816,728*
|
9
|
AGGREGATE
AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
816,728*
|
10
|
CHECK
BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES* ☐
|
11
|
PERCENT
OF CLASS REPRESENTED BY AMOUNT IN ROW 9
9.4%*
|
12
|
TYPE
OF REPORTING PERSON*
IN
|
|
|
|
|
|
|
|
Item
1(a).
|
Name
of Issuer:
|
aTyr Pharma, Inc.
|
Item
1(b).
|
Address
of Issuer’s Principal Executive Offices:
|
3545 John Hopkins Court, Suite #250
San
Diego, California 92121
|
Item
2(a).
|
Name
of Person Filing:
|
Viking
Global Investors LP (“VGI”),
Viking Global Opportunities GP LLC (“Opportunities GP”),
Viking Global Opportunities Portfolio GP LLC (“Opportunities Portfolio GP”),
Viking Global Opportunities Illiquid Investments Sub-Master LP (“VGOP”),
O. Andreas Halvorsen, David C. Ott and Rose S. Shabet (collectively, the “Reporting Persons”)
|
Items
2(b).
|
Address
of Principal Business Office or, if none, Residence:
|
The
business address of each of the Reporting Persons is: 55 Railroad Avenue, Greenwich, Connecticut 06830.
VGI is a Delaware limited partnership; Opportunities GP and Opportunities Portfolio GP are Delaware limited liability companies; VGOP is a Cayman Islands exempted limited partnership; O. Andreas Halvorsen is a citizen of Norway; and David C. Ott and Rose S. Shabet are citizens of the United States.
|
Item
2(d).
|
Titles
of Classes of Securities:
|
Common
stock, par value $0.001 per share (“Common Stock”)
|
Item
2(e).
|
CUSIP
NUMBER: 002120103
|
|
Item
3.
|
If This Statement is Filed Pursuant to Rule
13d-1(b), or 13d-2(b) or (c), Check Whether the Person Filing is a:
|
|
(a)
|
☐ Broker or dealer registered under Section 15 of the Exchange Act.
|
|
(b)
|
☐ Bank as defined in Section 3(a)(6) of the Exchange Act.
|
|
(c)
|
☐ Insurance company as defined in Section 3(a)(19) of the Exchange Act.
|
|
(d)
|
☐ Investment company registered under
Section 8 of the Investment Company Act of 1940.
|
|
(e)
|
☐ Investment Adviser registered under Section 203 of the Investment Advisers Act of 1940:
see Rule 13d-1(b)(1)(ii)(E).
|
|
(f)
|
☐ Employee Benefit Plan, Pension Fund which is subject to the provisions of the Employee
Retirement Income Security Act of 1974 or Endowment Fund; see Rule 13d-1(b)(1)(ii)(F).
|
|
(g)
|
☐ Parent holding company, in accordance with Rule 13d-1(b)(1)(ii)(G).
|
|
(h)
|
☐ Savings Association as defined in Section 3(b) of the Federal Deposit Insurance Act.
|
|
(i)
|
☐ Church Plan that is excluded from the definition of an investment company under Section
3(c)(14) of the Investment Company Act of 1940.
|
|
(j)
|
☐ Non-U.S. institution in accordance with Rule 240.13d-1(b)(1)(ii)(J). If filing as a
non-U.S. institution in accordance with Rule 240.13d-1(b)(1)(ii)(J), please specify the
type of institution:
|
|
(k)
|
☐ Group, in accordance with Rule 240.13d-1(b)(1)(ii)(K).
|
A.
VGI
|
(a)
|
Amount
beneficially owned: 816,728
|
|
(b)
|
Percent
of Class: 9.4%
|
|
(c)
|
Number
of shares as to which such person has:
|
|
(i)
|
Sole
power to vote or to direct the vote: 0
|
|
(ii)
|
Shared
power to vote or to direct the vote: 816,728
|
|
(iii)
|
Sole
power to dispose or to direct the disposition of: 0
|
|
(iv)
|
Shared
power to dispose or to direct the disposition of: 816,728
|
VGI provides managerial services to VGOP. VGI has the authority to dispose of and vote the shares of Common Stock.
Based on Rule 13d-3 of the Securities Exchange Act of 1934, as amended (the "Act"), VGI may be deemed to beneficially own the shares of Common Stock directly held by VGOP. VGI does not directly own any shares of Common Stock.
VGI beneficially owns 816,728 shares of Common Stock consisting of (i) 229,283 shares of Common Stock directly and beneficially owned by VGOP and (ii) 587,445 shares of Common Stock underlying Class X Preferred Stock, par value $0.001 per share (the “Preferred Stock”) directly and beneficially owned by VGOP.
B.
Opportunities GP
|
(a)
|
Amount
beneficially owned: 816,728
|
|
(b)
|
Percent
of Class: 9.4%
|
|
(c)
|
Number
of shares as to which such person has:
|
|
(i)
|
Sole
power to vote or to direct the vote: 0
|
|
(ii)
|
Shared
power to vote or to direct the vote: 816,728
|
|
(iii)
|
Sole
power to dispose or to direct the disposition of: 0
|
|
(iv)
|
Shared
power to dispose or to direct the disposition of: 816,728
|
Opportunities GP serves as the sole member of Opportunities Portfolio GP and has the authority to dispose of and vote the
shares of Common Stock controlled by Opportunities Portfolio GP, which consists of the shares of Common Stock directly held
by VGOP. Opportunities GP does not directly own any shares of Common Stock.
Based on Rule 13d-3 of the Act, Opportunities GP may be deemed to beneficially own the shares of Common Stock controlled by Opportunities Portfolio GP, which consists of the shares of Common Stock directly held by VGOP.
Opportunities GP beneficially owns 816,728 shares of Common Stock consisting of (i) 229,283 shares of Common Stock directly and beneficially owned by VGOP and (ii) 587,445 shares of Common Stock underlying the Preferred Stock directly and beneficially owned by VGOP.
C.
Opportunities Portfolio GP
|
(a)
|
Amount
beneficially owned: 816,728
|
|
(b)
|
Percent
of Class: 9.4%
|
|
(c)
|
Number
of shares as to which such person has:
|
|
(i)
|
Sole
power to vote or to direct the vote: 0
|
|
(ii)
|
Shared
power to vote or to direct the vote: 816,728
|
|
(iii)
|
Sole
power to dispose or to direct the disposition of: 0
|
|
(iv)
|
Shared
power to dispose or to direct the disposition of: 816,728
|
Opportunities Portfolio GP serves as the general partner of VGOP and has the authority to dispose of and vote the shares of Common Stock directly owned by VGOP. Opportunities Portfolio GP does not directly own any shares of Common Stock.
Based on Rule 13d-3 of the Act, Opportunities Portfolio GP may be
deemed to beneficially own the shares of Common Stock directly held by VGOP.
Opportunities Portfolio GP beneficially owns 816,728
shares of Common Stock consisting of (i) 229,283 shares of Common Stock directly and beneficially owned by VGOP and (ii) 587,445
shares of Common Stock underlying the Preferred Stock directly and beneficially owned by VGOP.
D.
VGOP
|
(a)
|
Amount
beneficially owned: 816,728
|
|
(b)
|
Percent
of Class: 9.74
|
|
(c)
|
Number
of shares as to which such person has:
|
|
(i)
|
Sole
power to vote or to direct the vote: 0
|
|
(ii)
|
Shared
power to vote or to direct the vote: 816,728
|
|
(iii)
|
Sole
power to dispose or to direct the disposition of: 0
|
|
(iv)
|
Shared
power to dispose or to direct the disposition of: 816,728
|
VGOP has the authority to dispose of and vote the shares of Common Stock directly owned by it, which power may be exercised
by its general partner, Opportunities Portfolio GP, and by VGI, an affiliate of Opportunities Portfolio GP, which provides
managerial services to VGOP. Viking Global Opportunities LP (a Delaware limited partnership) and Viking Global Opportunities
III LP (a Cayman Islands exempted limited partnership), through its investment in Viking Global Opportunities Intermediate
L.P. (a Cayman Islands exempted limited partnership), invest substantially all of their assets in Viking Global Opportunities
Master LP (a Cayman Islands exempted limited partnership), which in turn invests through VGOP.
VGOP
directly and beneficially owns 816,728 shares of Common Stock consisting of (i) 229,283 shares of Common Stock directly and beneficially
owned by VGOP and (ii) 587,445 shares of Common Stock underlying the Preferred Stock directly and beneficially owned by VGOP.
E.
O. Andreas Halvorsen, David C. Ott and Rose S. Shabet:
|
(a)
|
Amount
beneficially owned: 816,728
|
|
(b)
|
Percent of Class: 9.4%
|
|
(c)
|
Number
of shares as to which such person has:
|
|
(i)
|
Sole
power to vote or to direct the vote: 0
|
|
(ii)
|
Shared
power to vote or to direct the vote: 816,728
|
|
(iii)
|
Sole
power to dispose or to direct the disposition of: 0
|
|
(iv)
|
Shared
power to dispose or to direct the disposition of: 816,728
|
Mr. Halvorsen, Mr. Ott and Ms. Shabet, as Executive
Committee Members of Viking Global Partners LLC, general partner of VGI and Opportunities GP have shared authority to dispose
of and vote the shares of Common Stock beneficially owned by VGI and Opportunities GP. None of Mr. Halvorsen, Mr. Ott and Ms.
Shabet directly owns any shares of Common Stock.
Based on Rule 13d-3 of the Act, each may be deemed to beneficially
own the shares of Common Stock directly held by VGOP.
Mr.
Halvorsen, Mr. Ott and Ms. Shabet each beneficially own 816,728 shares of Common Stock consisting of (i) 229,283 shares of
Common Stock directly and beneficially owned by VGOP and (ii) 587,445 shares of Common Stock underlying the Preferred Stock
directly and beneficially owned by VGOP.
The
percentage of the class of Common Stock beneficially owned by each Reporting Person is calculated based upon (i) 8,125,479
shares of Common Stock to be issued and outstanding after the Issuer’s public offering, as reported by the Issuer in
its registration statement on Form S-1 filed with the Securities and Exchange Commission (the “Commission”) on
January 27, 2020 and (ii) the 587,445 shares of Common Stock underlying shares of Preferred Stock that could be converted by
VGOP without violating the Beneficial Ownership Limitation.
|
Item
5.
|
Ownership
of Five Percent or Less of a Class.
|
If this statement is being filed to report the fact that as of the date hereof the Reporting Persons have ceased to be the beneficial owner of more than five percent of the class of securities, check the following ☐.
|
Item
6.
|
Ownership
of More than Five Percent on Behalf of Another Person.
|
Yes,
see Item 4.
|
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. (if filing pursuant to Rule 13d-1(c))
|
By signing below each Reporting Person certifies that, to the best of its 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 not held in connection with or as a participant in any transaction having that purpose or effect.
SIGNATURES
After
reasonable inquiry and to the best of our knowledge and belief, the undersigned certify that the information set forth in this
statement is true, complete and correct.
Dated:
February 11, 2020
/s/
O. ANDREAS HALVORSEN
By: O. Andreas Halvorsen - individually and as an Executive Committee Member of VIKING GLOBAL PARTNERS LLC,
on behalf of VIKING GLOBAL INVESTORS LP, and as an Executive Committee Member of VIKING GLOBAL OPPORTUNITIES GP LLC, on behalf
of itself and VIKING GLOBAL OPPORTUNITIES PORTFOLIO GP LLC and VIKING GLOBAL OPPORTUNITIES ILLIQUID INVESTMENTS SUB-MASTER LP
/s/
DAVID C. OTT
By: David C. Ott - individually and as an Executive Committee Member of VIKING GLOBAL PARTNERS LLC, on behalf of
VIKING GLOBAL INVESTORS LP, and as an Executive Committee Member of VIKING GLOBAL OPPORTUNITIES GP LLC, on behalf of itself and
VIKING GLOBAL OPPORTUNITIES PORTFOLIO GP LLC and VIKING GLOBAL OPPORTUNITIES ILLIQUID INVESTMENTS SUB-MASTER LP
/s/
ROSE S. SHABET
By: Rose S. Shabet - individually and as an Executive Committee Member of VIKING GLOBAL PARTNERS LLC, on
behalf of VIKING GLOBAL INVESTORS LP, and as an Executive Committee Member of VIKING GLOBAL OPPORTUNITIES GP LLC, on behalf
of itself and VIKING GLOBAL OPPORTUNITIES PORTFOLIO GP LLC and VIKING GLOBAL OPPORTUNITIES ILLIQUID INVESTMENTS SUB-MASTER LP