SEC FORM 3

SEC Form 3

FORM 3

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940

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1. Name and Address of Reporting Person^*

BAKER BROS. ADVISORS LP

(Last)

(First)

(Middle)

860 WASHINGTON STREET

3RD FLOOR

(Street)

NEW YORK

10014

(City)

(State)

(Zip)

2. Date of Event Requiring Statement (Month/Day/Year)
09/13/2018

3. Issuer Name and Ticker or Trading Symbol
Principia Biopharma Inc. [ PRNB ]

4. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

Director	X	10% Owner
Officer (give title below)		Other (specify below)

5. If Amendment, Date of Original Filed (Month/Day/Year)

6. Individual or Joint/Group Filing (Check Applicable Line)

	Form filed by One Reporting Person
X	Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Beneficially Owned
1. Title of Security (Instr. 4)	2. Amount of Securities Beneficially Owned (Instr. 4)	3. Ownership Form: Direct (D) or Indirect (I) (Instr. 5)	4. Nature of Indirect Beneficial Ownership (Instr. 5)

Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 4)	2. Date Exercisable and Expiration Date (Month/Day/Year)		3. Title and Amount of Securities Underlying Derivative Security (Instr. 4)		4. Conversion or Exercise Price of Derivative Security	5. Ownership Form: Direct (D) or Indirect (I) (Instr. 5)	6. Nature of Indirect Beneficial Ownership (Instr. 5)
1. Title of Derivative Security (Instr. 4)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares	4. Conversion or Exercise Price of Derivative Security	5. Ownership Form: Direct (D) or Indirect (I) (Instr. 5)	6. Nature of Indirect Beneficial Ownership (Instr. 5)
Series B-1 Convertible Preferred	⁽¹⁾	⁽¹⁾	Common Stock	57,262	$0⁽¹⁾	I	See Footnotes⁽²⁾⁽¹⁶⁾⁽¹⁷⁾
Series B-1 Convertible Preferred	⁽¹⁾	⁽¹⁾	Common Stock	554,561	$0⁽¹⁾	I	See Footnotes⁽³⁾⁽¹⁶⁾⁽¹⁷⁾
Series B-1 Convertible Preferred	⁽¹⁾	⁽¹⁾	Common Stock	13,658	$0⁽¹⁾	I	See Footnotes⁽⁴⁾⁽¹⁶⁾⁽¹⁷⁾
Series B-2 Convertible Preferred	⁽¹⁾	⁽¹⁾	Common Stock	50,506	$0⁽¹⁾	I	See Footnotes⁽⁵⁾⁽¹⁶⁾⁽¹⁷⁾
Series B-2 Convertible Preferred	⁽¹⁾	⁽¹⁾	Common Stock	470,728	$0⁽¹⁾	I	See Footnotes⁽⁶⁾⁽¹⁶⁾⁽¹⁷⁾
Series B-3 Convertible Preferred	⁽¹⁾	⁽¹⁾	Common Stock	37,745	$0⁽¹⁾	I	See Footnotes⁽⁷⁾⁽¹⁶⁾⁽¹⁷⁾
Series B-3 Convertible Preferred	⁽¹⁾	⁽¹⁾	Common Stock	413,734	$0⁽¹⁾	I	See Footnotes⁽⁸⁾⁽¹⁶⁾⁽¹⁷⁾
Series B-3 Convertible Preferred	⁽¹⁾	⁽¹⁾	Common Stock	2,473	$0⁽¹⁾	I	See Footnotes⁽⁹⁾⁽¹⁶⁾⁽¹⁷⁾
Series C Convertible Preferred	⁽¹⁾	⁽¹⁾	Common Stock	6,980	$0⁽¹⁾	I	See Footnotes⁽¹⁰⁾⁽¹⁶⁾⁽¹⁷⁾
Series C Convertible Preferred	⁽¹⁾	⁽¹⁾	Common Stock	62,513	$0⁽¹⁾	I	See Footnotes⁽¹¹⁾⁽¹⁶⁾⁽¹⁷⁾
Warrant to Purchase Series B-3 Convertible Preferred Stock	⁽¹²⁾	12/29/2022	Series B-3 Preferred Stock	1,903	$8.9931	I	See Footnotes⁽¹³⁾⁽¹⁶⁾⁽¹⁷⁾
Warrant to Purchase Series B-3 Convertible Preferred Stock	⁽¹²⁾	12/29/2022	Series B-3 Preferred Stock	18,824	$8.9931	I	See Footnotes⁽¹⁴⁾⁽¹⁶⁾⁽¹⁷⁾
Warrant to Purchase Series B-3 Convertible Preferred Stock	⁽¹²⁾	12/29/2022	Series B-3 Preferred Stock⁽¹⁾	211	$8.9931	I	See Footnotes⁽¹⁵⁾⁽¹⁶⁾⁽¹⁷⁾

1. Name and Address of Reporting Person^*

BAKER BROS. ADVISORS LP

(Last)

(First)

(Middle)

860 WASHINGTON STREET

3RD FLOOR

(Street)

NEW YORK

10014

(City)

(State)

(Zip)

Relationship of Reporting Person(s) to Issuer

Director	X	10% Owner
Officer (give title below)		Other (specify below)

1. Name and Address of Reporting Person^*

Baker Bros. Advisors (GP) LLC

(Last)

(First)

(Middle)

860 WASHINGTON STREET

3RD FLOOR

(Street)

NEW YORK

10014

(City)

(State)

(Zip)

Relationship of Reporting Person(s) to Issuer

Director	X	10% Owner
Officer (give title below)		Other (specify below)

1. Name and Address of Reporting Person^*

BAKER FELIX

(Last)

(First)

(Middle)

860 WASHINGTON STREET

3RD FLOOR

(Street)

NEW YORK

10014

(City)

(State)

(Zip)

Relationship of Reporting Person(s) to Issuer

Director	X	10% Owner
Officer (give title below)		Other (specify below)

1. Name and Address of Reporting Person^*

BAKER JULIAN

(Last)

(First)

(Middle)

860 WASHINGTON STREET, 3RD FLOOR

(Street)

NEW YORK

10014

(City)

(State)

(Zip)

Relationship of Reporting Person(s) to Issuer

Director	X	10% Owner
Officer (give title below)		Other (specify below)

Explanation of Responses:

1. These securities consist of Series B-1 Convertible Preferred Shares ("Series B-1 Preferred"), Series B-2 Convertible Preferred Shares ("Series B-2 Preferred"), Series B-3 Convertible Preferred ("Series B-3 Preferred") and Series C Convertible Preferred ("Series C Preferred", and together with Series B-1 Preferred, Series B-2 Preferred and Series B-3 Preferred, the "Preferred Shares") of Principia Pharmaceuticals Inc. (the "Issuer") which are convertible into the Issuer's common stock ("Common Stock") on a 1 for 1 basis (the "Preferred Conversion Ratio") at any time at the election of the holder and will automatically convert at the Preferred Conversion Ratio into the number of shares of Common Stock shown in column 3, without payment or further consideration upon the closing of the Issuer's initial public offering. The Preferred Shares have no expiration date.

2. As a result of Felix J. Baker's and Julian C. Baker's ownership interest in Baker Biotech Capital (GP), LLC, Felix J. Baker and Julian C. Baker may be deemed to have an indirect pecuniary interest in 57,262 shares of Series B-1 Preferred held directly by 667, L.P. ("667"), a limited partnership of which the sole general partner is Baker Biotech Capital, L.P., a limited partnership of which the sole general partner is Baker Biotech Capital (GP), LLC, due to Baker Biotech Capital, L.P.'s right to receive an allocation of a portion of the profits from 667.

3. As a result of Felix J. Baker's and Julian C. Baker's ownership interest in Baker Brothers Life Sciences Capital (GP), LLC, Felix J. Baker and Julian C. Baker may be deemed to have an indirect pecuniary interest in 554,561 shares of Series B-1 Preferred held directly by Baker Brothers Life Sciences, L.P. ("Life Sciences"), a limited partnership of which the sole general partner is Baker Brothers Life Sciences Capital, L.P., a limited partnership of which the sole general partner is Baker Brothers Life Sciences Capital (GP), LLC, due to Baker Brothers Life Sciences Capital, L.P.'s right to receive an allocation of a portion of the profits from Life Sciences.

4. As a result of Felix J. Baker's and Julian C. Baker's ownership interest in 14159 Capital (GP), LLC, Felix J. Baker and Julian C. Baker may be deemed to have an indirect pecuniary interest in 13,658 shares of Series B-1 Preferred held directly by 14159, L.P. ("14159", and together with 667 and Life Sciences, the "Funds"), a limited partnership of which the sole general partner is 14159 Capital, L.P., a limited partnership of which the sole general partner is 14159 Capital (GP), LLC, due to 14159 Capital, L.P.'s right to receive an allocation of a portion of the profits from 14159.

5. As a result of Felix J. Baker's and Julian C. Baker's ownership interest in Baker Biotech Capital (GP), LLC, Felix J. Baker and Julian C. Baker may be deemed to have an indirect pecuniary interest in 50,506 shares of Series B-2 Preferred held directly by 667, a limited partnership of which the sole general partner is Baker Biotech Capital, L.P., a limited partnership of which the sole general partner is Baker Biotech Capital (GP), LLC, due to Baker Biotech Capital, L.P.'s right to receive an allocation of a portion of the profits from 667.

6. As a result of Felix J. Baker's and Julian C. Baker's ownership interest in Baker Brothers Life Sciences Capital (GP), LLC, Felix J. Baker and Julian C. Baker may be deemed to have an indirect pecuniary interest in 470,728 shares of Series B-2 Preferred held directly by Life Sciences, a limited partnership of which the sole general partner is Baker Brothers Life Sciences Capital, L.P., a limited partnership of which the sole general partner is Baker Brothers Life Sciences Capital (GP), LLC, due to Baker Brothers Life Sciences Capital, L.P.'s right to receive an allocation of a portion of the profits from Life Sciences.

7. As a result of Felix J. Baker's and Julian C. Baker's ownership interest in Baker Biotech Capital (GP), LLC, Felix J. Baker and Julian C. Baker may be deemed to have an indirect pecuniary interest in 37,745 shares of Series B-3 Preferred held directly by 667, a limited partnership of which the sole general partner is Baker Biotech Capital, L.P., a limited partnership of which the sole general partner is Baker Biotech Capital (GP), LLC, due to Baker Biotech Capital, L.P.'s right to receive an allocation of a portion of the profits from 667.

8. As a result of Felix J. Baker's and Julian C. Baker's ownership interest in Baker Brothers Life Sciences Capital (GP), LLC, Felix J. Baker and Julian C. Baker may be deemed to have an indirect pecuniary interest in 413,734 shares of Series B-3 Preferred held directly by Life Sciences, a limited partnership of which the sole general partner is Baker Brothers Life Sciences Capital, L.P., a limited partnership of which the sole general partner is Baker Brothers Life Sciences Capital (GP), LLC, due to Baker Brothers Life Sciences Capital, L.P.'s right to receive an allocation of a portion of the profits from Life Sciences.

9. As a result of Felix J. Baker's and Julian C. Baker's ownership interest in 14159 Capital (GP), LLC, Felix J. Baker and Julian C. Baker may be deemed to have an indirect pecuniary interest in 2,473 shares of Series B-3 Preferred held directly by 14159, a limited partnership of which the sole general partner is 14159 Capital, L.P., a limited partnership of which the sole general partner is 14159 Capital (GP), LLC, due to 14159 Capital, L.P.'s right to receive an allocation of a portion of the profits from 14159.

10. As a result of Felix J. Baker's and Julian C. Baker's ownership interest in Baker Biotech Capital (GP), LLC, Felix J. Baker and Julian C. Baker may be deemed to have an indirect pecuniary interest in 6,980 shares of Series C Preferred held directly by 667, a limited partnership of which the sole general partner is Baker Biotech Capital, L.P., a limited partnership of which the sole general partner is Baker Biotech Capital (GP), LLC, due to Baker Biotech Capital, L.P.'s right to receive an allocation of a portion of the profits from 667.

11. As a result of Felix J. Baker's and Julian C. Baker's ownership interest in Baker Brothers Life Sciences Capital (GP), LLC, Felix J. Baker and Julian C. Baker may be deemed to have an indirect pecuniary interest in 62,513 shares of Series C Preferred held directly by Life Sciences, a limited partnership of which the sole general partner is Baker Brothers Life Sciences Capital, L.P., a limited partnership of which the sole general partner is Baker Brothers Life Sciences Capital (GP), LLC, due to Baker Brothers Life Sciences Capital, L.P.'s right to receive an allocation of a portion of the profits from Life Sciences.

12. The warrants are exercisable at any time.

13. As a result of Felix J. Baker's and Julian C. Baker's ownership interest in Baker Biotech Capital (GP), LLC, Felix J. Baker and Julian C. Baker may be deemed to have an indirect pecuniary interest in 1,903 warrants to purchase Series B-3 Preferred held directly by 667, a limited partnership of which the sole general partner is Baker Biotech Capital, L.P., a limited partnership of which the sole general partner is Baker Biotech Capital (GP), LLC, due to Baker Biotech Capital, L.P.'s right to receive an allocation of a portion of the profits from 667.

14. As a result of Felix J. Baker's and Julian C. Baker's ownership interest in Baker Brothers Life Sciences Capital (GP), LLC, Felix J. Baker and Julian C. Baker may be deemed to have an indirect pecuniary interest in 18,824 warrants to purchase Series B-3 Preferred held directly by Life Sciences, a limited partnership of which the sole general partner is Baker Brothers Life Sciences Capital, L.P., a limited partnership of which the sole general partner is Baker Brothers Life Sciences Capital (GP), LLC, due to Baker Brothers Life Sciences Capital, L.P.'s right to receive an allocation of a portion of the profits from Life Sciences.

15. As a result of Felix J. Baker's and Julian C. Baker's ownership interest in 14159 Capital (GP), LLC, Felix J. Baker and Julian C. Baker may be deemed to have an indirect pecuniary interest in 211 warrants to purchase Series B-3 Preferred held directly by 14159, a limited partnership of which the sole general partner is 14159 Capital, L.P., a limited partnership of which the sole general partner is 14159 Capital (GP), LLC, due to 14159 Capital, L.P.'s right to receive an allocation of a portion of the profits from 14159.

16. Baker Bros. Advisors LP (the "Adviser") serves as the Investment Adviser to the Funds. In connection with the services provided by the Adviser, the Adviser receives an asset-based management fee that does not confer any pecuniary interest in the securities held by the Funds. Baker Bros. Advisors (GP) LLC (the "Adviser GP") is the Adviser's sole general partner. Julian C. Baker and Felix J. Baker are principals of the Adviser GP. The Adviser has complete and unlimited discretion and authority with respect to the investment and voting power of the securities held by the Funds.

17. The general partners of the Funds relinquished to the Adviser all discretion and authority with respect to the investment and voting power of the securities held by the Funds. Julian C. Baker, Felix J. Baker, the Adviser GP and the Adviser disclaim beneficial ownership of the securities held directly by the Funds except to the extent of their pecuniary interest therein, and this report shall not be deemed an admission that any of Julian C. Baker, Felix J. Baker, the Adviser GP or the Adviser is a beneficial owner of such securities for purposes of Section 16 or any other purpose.

Remarks:

	By: Baker Bros. Advisors LP, Name: Scott L. Lessing /s/ Scott L. Lessing	09/13/2018
	By: Baker Bros. Advisors (GP) LLC, Name: Scott L. Lessing /s/ Scott L. Lessing	09/13/2018
	/s/ Felix J. Baker	09/13/2018
	/s/ Julian C. Baker	09/13/2018
	** Signature of Reporting Person	Date
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