SEC Form 4

FORM 4		UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934 or Section 30(h) of the Investment Company Act of 1940	OMB APPROVAL OMB Number: 3235-0287 Estimated average burden hours per response: 0.5
	Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

1. Name and Address of Reporting Person* BVF PARTNERS L P/IL (Last) (First) (Middle) 44 MONTGOMERY STREET 40TH FLOOR (Street) SAN FRANCISCO CA 94104 (City) (State) (Zip)	2. Issuer Name and Ticker or Trading Symbol XOMA Corp [ XOMA ]	5. Relationship of Reporting Person(s) to Issuer (Check all applicable) Director X 10% Owner Officer (give title below) Other (specify below)
	3. Date of Earliest Transaction (Month/Day/Year) 12/18/2019
	4. 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 Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price
Common Stock, $0.0075 par value per share(1)	12/18/2019		X		245,481(8)	A	$22	940,442	D(2)
Common Stock, $0.0075 par value per share(1)	12/18/2019		X		190,899(8)	A	$22	937,353	D(3)
Common Stock, $0.0075 par value per share(1)	12/18/2019		X		35,888(8)	A	$22	159,537	D(4)
Common Stock, $0.0075 par value per share(1)	12/19/2019		P		207,234(9)	A	$22	1,147,676	D(2)
Common Stock, $0.0075 par value per share(1)	12/19/2019		P		165,961(9)	A	$22	1,103,314	D(3)
Common Stock, $0.0075 par value per share(1)								231,878	I(5)	See footnote(5)

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares
Subscription Rights (right to buy)	$22	12/18/2019		X			245,481	12/02/2019	12/18/2019	Common Stock, $0.0075 par value per share	245,481	$0	0	D(2)
Subscription Rights (right to buy)	$22	12/18/2019		X			190,899	12/02/2019	12/18/2019	Common Stock, $0.0075 par value per share	190,899	$0	0	D(3)
Subscription Rights (right to buy)	$22	12/18/2019		X			35,888	12/02/2019	12/18/2019	Common Stock, $0.0075 par value per share	35,888	$0	0	D(4)
Series X Convertible Preferred Stock	(6)							(6)	(6)	Common Stock, $0.0075 par value per share	2,313,000		2,313	D(2)
Series X Convertible Preferred Stock	(6)							(6)	(6)	Common Stock, $0.0075 par value per share	1,506,000		1,506	D(3)
Series X Convertible Preferred Stock	(6)							(6)	(6)	Common Stock, $0.0075 par value per share	412,000		412	D(4)
Series X Convertible Preferred Stock	(6)							(6)	(6)	Common Stock, $0.0075 par value per share	772,000		772	I(5)	See footnote(5)
Series Y Convertible Preferred Stock	(7)							(7)	(7)	Common Stock, $0.0075 par value per share	655,959		655.959	D(2)
Series Y Convertible Preferred Stock	(7)							(7)	(7)	Common Stock, $0.0075 par value per share	596,813		596.813	D(3)

1. Name and Address of Reporting Person* BVF PARTNERS L P/IL (Last) (First) (Middle) 44 MONTGOMERY STREET 40TH FLOOR (Street) SAN FRANCISCO CA 94104 (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* BIOTECHNOLOGY VALUE FUND L P (Last) (First) (Middle) 44 MONTGOMERY STREET 40TH FLOOR (Street) SAN FRANCISCO CA 94104 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director 10% Owner Officer (give title below) X Other (specify below) See Explanation of Responses

1. Name and Address of Reporting Person* BIOTECHNOLOGY VALUE FUND II LP (Last) (First) (Middle) 44 MONTGOMERY STREET 40TH FLOOR (Street) SAN FRANCISCO CA 94104 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director 10% Owner Officer (give title below) X Other (specify below) See Explanation of Responses

1. Name and Address of Reporting Person* Biotechnology Value Trading Fund OS LP (Last) (First) (Middle) P.O. BOX 309 UGLAND HOUSE (Street) GRAND CAYMAN E9 KY1-1104 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director 10% Owner Officer (give title below) X Other (specify below) See Explanation of Responses

1. Name and Address of Reporting Person* BVF Partners OS Ltd. (Last) (First) (Middle) P.O. BOX 309 UGLAND HOUSE (Street) GRAND CAYMAN E9 KY1-1104 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director 10% Owner Officer (give title below) X Other (specify below) See Explanation of Responses

1. Name and Address of Reporting Person* BVF INC/IL (Last) (First) (Middle) 44 MONTGOMERY STREET 40TH FLOOR (Street) SAN FRANCISCO CA 94104 (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* LAMPERT MARK N (Last) (First) (Middle) 44 MONTGOMERY STREET 40TH FLOOR (Street) SAN FRANCISCO CA 94104 (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. This Form 4 is filed jointly by Biotechnology Value Fund, L.P. ("BVF"), Biotechnology Value Fund II, L.P. ("BVF2"), Biotechnology Value Trading Fund OS LP ("Trading Fund OS"), BVF Partners OS Ltd. ("Partners OS"), BVF Partners L.P. ("Partners"), BVF Inc. and Mark N. Lampert (collectively, the "Reporting Persons"). Each of the Reporting Persons is a member of a Section 13(d) group that collectively owns more than 10% of the Issuer's outstanding shares of Common Stock. Each of the Reporting Persons disclaims beneficial ownership of the shares of the Common Stock reported herein except to the extent of his or its pecuniary interest therein.

2. Securities owned directly by BVF. As the general partner of BVF, Partners may be deemed to beneficially own the securities owned directly by BVF. As the investment adviser and general partner of Partners, BVF Inc. may be deemed to beneficially own the securities owned directly by BVF. As a director and officer of BVF Inc., Mr. Lampert may be deemed to beneficially own the securities owned directly by BVF.

3. Securities owned directly by BVF2. As the general partner of BVF2, Partners may be deemed to beneficially own the securities owned directly by BVF2. As the investment adviser and general partner of Partners, BVF Inc. may be deemed to beneficially own the securities owned directly by BVF2. As a director and officer of BVF Inc., Mr. Lampert may be deemed to beneficially own the securities owned directly by BVF2.

4. Securities owned directly by Trading Fund OS. As the general partner of Trading Fund OS, Partners OS may be deemed to beneficially own the securities owned directly by Trading Fund OS. As the investment manager of Trading Fund OS and the sole member of Partners OS, Partners may be deemed to beneficially own the securities owned directly by Trading Fund OS. As the investment adviser and general partner of Partners, BVF Inc. may be deemed to beneficially own the securities owned directly by Trading Fund OS. As a director and officer of BVF Inc., Mr. Lampert may be deemed to beneficially own the securities owned directly by Trading Fund OS.

5. Securities held in certain Partners managed accounts (the "Partners Managed Accounts"). Partners, as the investment manager of the Partners Managed Accounts, may be deemed to beneficially own the securities held by the Partners Managed Accounts. As the investment adviser and general partner of Partners, BVF Inc. may be deemed to beneficially own the securities held by the Partners Managed Accounts. As a director and officer of BVF Inc., Mr. Lampert may be deemed to beneficially own the securities held by the Partners Managed Accounts.

6. The Series X Convertible Preferred Stock may not be exercised if, after such exercise, the Reporting Persons would beneficially own, as determined in accordance with Section 13(d), more than 19.99% of the shares of Common Stock outstanding immediately after giving effect to such exercise. The Series X Convertible Preferred Stock does not have an expiration date. The initial conversion price is $4.03 and is subject to certain adjustments pursuant to the Certificate of Designation of Preferences, Rights and Limitations of Series X Convertible Preferred Stock.

7. The Series Y Convertible Preferred Stock may not be exercised if, after such exercise, the Reporting Persons would beneficially own, as determined in accordance with Section 13(d), more than 19.99% of the shares of Common Stock outstanding immediately after giving effect to such exercise. The Series Y Convertible Preferred Stock does not have an expiration date. The initial conversion price is $13.00 and is subject to certain adjustments pursuant to the Certificate of Designation of Preferences, Rights and Limitations of Series Y Convertible Preferred Stock.

8. Shares of Common Stock acquired following the exercise of such Reporting Person's basic subscription privilege in the Issuer's rights offering (the "Offering").

9. Shares of Common Stock acquired pursuant to the terms and conditions of a backstop commitment made by certain of the Reporting Persons in connection with the Offering.

	BVF Partners L.P., By: BVF Inc., its general partner, By: /s/ Mark N. Lampert, President	12/20/2019
	Biotechnology Value Fund, L.P., By: BVF Partners L.P., its general partner, By: BVF Inc., its general partner, By: /s/ Mark N. Lampert, President	12/20/2019
	Biotechnology Value Fund II, L.P., By: BVF Partners L.P., its general partner, By: BVF Inc., its general partner, By: /s/ Mark N. Lampert, President	12/20/2019
	BVF Partners OS Ltd., By: BVF Partners L.P., its sole member, By: BVF Inc., its general partner, By: /s/ Mark N. Lampert, President	12/20/2019
	Biotechnology Value Trading Fund OS LP, By: BVF Partners L.P., its investment manager, BVF Inc., its general partner, By: /s/ Mark N. Lampert, President	12/20/2019
	BVF Inc., By: /s/ Mark N. Lampert, President	12/20/2019
	/s/ Mark N. Lampert	12/20/2019
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
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