Albireo Pharma (ALBO) SC 13G ALBIREO PHARMA / CARLSON CAPITAL L P ownership change

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 13G

Under the Securities Exchange Act of 1934

Albireo Pharma, Inc.

(Name of Issuer)

Common Stock, $0.01 par value per share

(Title of Class of Securities)

01345P106

(CUSIP Number)

February 17, 2023

(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 the disclosures provided in a prior cover page.

The information required in 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. 01345P106 SCHEDULE 13G Page 2  of 14 Pages

1	NAMES OF REPORTING PERSON   Double Black Diamond Offshore Ltd.
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   178,146
	7	SOLE DISPOSITIVE POWER   0
	8	SHARED DISPOSITIVE POWER   178,146

9	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON   178,146
10	CHECK IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES   ☐
11	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)   1.0%
12	TYPE OF REPORTING PERSON   CO

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CUSIP No. 01345P106 SCHEDULE 13G Page 3  of 14 Pages

1	NAMES OF REPORTING PERSON   Black Diamond Arbitrage Offshore Ltd.
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   632,155
	7	SOLE DISPOSITIVE POWER   0
	8	SHARED DISPOSITIVE POWER   632,155

9	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON   632,155
10	CHECK IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES   ☐
11	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)   3.0%
12	TYPE OF REPORTING PERSON   CO

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CUSIP No. 01345P106 SCHEDULE 13G Page 4  of 14 Pages

1	NAMES OF REPORTING PERSON   EDCA 2019 Fund, L.P.
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   208,795
	7	SOLE DISPOSITIVE POWER   0
	8	SHARED DISPOSITIVE POWER   208,795

9	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON   208,795
10	CHECK IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES   ☐
11	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)   1.0%
12	TYPE OF REPORTING PERSON   PN

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CUSIP No. 01345P106 SCHEDULE 13G Page 5  of 14 Pages

1	NAMES OF REPORTING PERSON   Corbin Hedged Equity Fund, L.P.
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   55,904
	7	SOLE DISPOSITIVE POWER   0
	8	SHARED DISPOSITIVE POWER   55,904

9	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON   55,904
10	CHECK IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES   ☐
11	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)   0.3%
12	TYPE OF REPORTING PERSON   PN

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CUSIP No. 01345P106 SCHEDULE 13G Page 6  of 14 Pages

1	NAMES OF REPORTING PERSON   Carlson Capital, L.P.
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   1,075,000
	7	SOLE DISPOSITIVE POWER   0
	8	SHARED DISPOSITIVE POWER   1,075,000

9	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON   1,075,000
10	CHECK IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES   ☐
11	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)   5.2%
12	TYPE OF REPORTING PERSON   PN, IA

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CUSIP No. 01345P106 SCHEDULE 13G Page 7  of 14 Pages

1	NAMES OF REPORTING PERSON   Asgard Investment Corp. II
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   1,075,000
	7	SOLE DISPOSITIVE POWER   0
	8	SHARED DISPOSITIVE POWER   1,075,000

9	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON   1,075,000
10	CHECK IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES   ☐
11	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)   5.2%
12	TYPE OF REPORTING PERSON   CO

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CUSIP No. 01345P106 SCHEDULE 13G Page 8  of 14 Pages

1	NAMES OF REPORTING PERSON   Clint D. Carlson
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   1,075,000
	7	SOLE DISPOSITIVE POWER   0
	8	SHARED DISPOSITIVE POWER   1,075,000

9	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON   1,075,000
10	CHECK IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES   ☐
11	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)   5.2%
12	TYPE OF REPORTING PERSON   IN

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Item 1(a). NAME OF ISSUER

Albireo Pharma, Inc., a Delaware corporation (the “Issuer”).

Item 1(b). ADDRESS OF ISSUER’S PRINCIPAL EXECUTIVE OFFICES

53 State Street, 19th Floor

Boston, MA 02109

Item 2(a). NAME OF PERSON FILING

This statement is filed by:

(i) Double Black Diamond Offshore Ltd., a Cayman Islands exempted company (the “Double Offshore”), with respect to Common Stock, par value $0.01 per share, of the Issuer (the “Common Stock”) held or beneficially owned directly by it;

(ii) Black Diamond Arbitrage Offshore Ltd., a Cayman Islands exempted company (“Arbitrage Offshore”), with respect to the Common Stock held or beneficially owned directly by it;

(iii) EDCA 2019 Fund, L.P., a Delaware limited partnership (“EDCA”), with respect to the Common Stock held or beneficially owned directly by it;

(iv) Corbin Hedged Equity Fund, L.P., a Delaware Limited Partnership (“Corbin,” and together with Double Offshore, Arbitrage Offshore and EDCA, the “Funds”), with respect to the Common Stock directly held by it;

(v) Carlson Capital, L.P., a Delaware limited partnership (“Carlson Capital”), which serves as the investment manager to the Funds with respect to any shares of Common Stock held by the Funds;

(vi) Asgard Investment Corp. II, a Delaware corporation (“Asgard II”), which serves as the general partner of Carlson Capital, with respect to the Common Stock directly held by the Funds; and

(vii) Mr. Clint D. Carlson, a United States citizen (“Mr. Carlson”), who is the sole stockholder of Asgard II and serves as president of Asgard II and Carlson Capital, with respect to the Common Stock directly held by the Funds.

The foregoing persons are hereinafter sometimes collectively referred to as the “Reporting Persons”.

The filing of this statement should not be construed as an admission that any of the Reporting Persons is, for the purposes of Section 13 of the Act, the beneficial owner of the Common Stock reported herein.

Item 2(b). ADDRESS OF PRINCIPAL BUSINESS OFFICE OR, IF NONE, RESIDENCE

The address of the principal business office of each of the Reporting Persons is 2100 McKinney Avenue, Suite 1900, Dallas, Texas 75201.

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Item 2(c). CITIZENSHIP

Carlson Capital, EDCA and Corbin are Delaware limited partnerships. Double Offshore and Arbitrage Offshore are Cayman Islands exempted company. Asgard II is a Delaware corporation. Mr. Carlson is a United States citizen.

Item 2(d). TITLE OF CLASS OF SECURITIES

Common Stock, par value $0.01 per share (the “Common Stock”).

Item 2(e). CUSIP No.

01345P106

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 association 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)	☐	A non-U.S. institution in accordance with § 240.13d-1(b)(1)(ii)(J).
(k)	☐	Group, in accordance with § 240.13d-1(b)(1)(ii)(K).

If filing as a non-U.S. institution in accordance with Section 240.13d-1(b)(1)(ii)(J), please specify the type of institution: ___________________

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Item 4. OWNERSHIP

A. Double Offshore:

(a) Amount beneficially owned: 178,146 shares of Common Stock

(b) Percent of class: 1.0%

(c) (i)      Sole power to vote or direct the vote: 0

(ii) Shared power to vote or direct the vote: 178,146

(iii) Sole power to dispose or direct the disposition: 0

(iv) Shared power to dispose or direct the disposition: 178,146

B. Arbitrage Offshore:

(a) Amount beneficially owned: 632,155 shares of Common Stock

(b) Percent of class: 3.0%

(c) (i)      Sole power to vote or direct the vote: 0

(ii) Shared power to vote or direct the vote: 632,155

(iii) Sole power to dispose or direct the disposition: 0

(iv) Shared power to dispose or direct the disposition: 632,155

C. EDCA:

(a) Amount beneficially owned: 208,795 shares of Common Stock

(b) Percent of class: 1.0%

(c) (i)      Sole power to vote or direct the vote: 0

(ii) Shared power to vote or direct the vote: 208,795

(iii) Sole power to dispose or direct the disposition: 0

(iv) Shared power to dispose or direct the disposition: 208,795

D. Corbin:

(a) Amount beneficially owned: 55,904 shares of Common Stock

(b) Percent of class: 0.3%

(c) (i)      Sole power to vote or direct the vote: 0

(ii) Shared power to vote or direct the vote: 55,904

(iii) Sole power to dispose or direct the disposition: 0

(iv) Shared power to dispose or direct the disposition: 55,904

E. Carlson Capital:

(a) Amount beneficially owned: 1,075,000

(b) Percent of class: 5.2%

(c) (i)      Sole power to vote or direct the vote: 0

(ii) Shared power to vote or direct the vote: 1,075,000

(iii) Sole power to dispose or direct the disposition: 0

(iv) Shared power to dispose or direct the disposition: 1,075,000

F. Asgard II:

(a) Amount beneficially owned: 1,075,000

(b) Percent of class: 5.2%

(c) (i)      Sole power to vote or direct the vote: 0

(ii) Shared power to vote or direct the vote: 1,075,000

(iii) Sole power to dispose or direct the disposition: 0

(iv) Shared power to dispose or direct the disposition: 1,075,000

G. Mr. Carlson:

(a) Amount beneficially owned: 1,075,000

(b) Percent of class: 5.2%

(c) (i)      Sole power to vote or direct the vote: 0

(ii) Shared power to vote or direct the vote: 1,075,000

(iii) Sole power to dispose or direct the disposition: 0

(iv) Shared power to dispose or direct the disposition: 1,075,000

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The percentages reported in this Schedule 13G are based on 20,863,673 shares of Common Stock outstanding as of January 20, 2023, as reported in the Issuer’s Tender Offer Statement filed with the Securities and Exchange Commission on January 23, 2023. In addition, as of February 23, 2023, the Reporting Persons’ beneficial ownership increased to 1,375,000.00 (6.6%) from 1,075,000 (5.2%) shares of Common Stock.

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 person has ceased to be the beneficial owner of more than 5 percent of the class of securities, check the following ☐.

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 OR CONTROL PERSON

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

Each of the Reporting Persons hereby makes the following certification:

By signing below, each Reporting Person certifies that, to the best of his or 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 are not held in connection with or as a participant in any transaction having that purpose or effect.

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SIGNATURES

After reasonable inquiry and to the best of his or its knowledge and belief, each of the undersigned certifies that the information set forth in this statement is true, complete and correct.

DATED: February 24, 2023

DOUBLE BLACK DIAMOND OFFSHORE LTD.
By: Carlson Capital, L.P., its investment manager
By: Asgard Investment Corp. II, its general partner
By:	/s/ Clint D. Carlson
Name:	Clint D. Carlson
Title:	President
BLACK DIAMOND ARBITRAGE OFFSHORE LTD.
By: Carlson Capital, L.P., its investment manager
By: Asgard Investment Corp. II, its general partner
By:	/s/ Clint D. Carlson
Name:	Clint D. Carlson
Title:	President
EDCA 2019 Fund, L.P.
By: Carlson Capital, L.P., its investment manager
By: Asgard Investment Corp. II, its general partner
By:	/s/ Clint D. Carlson
Name:	Clint D. Carlson
Title:	President
CORBIN HEDGED EQUITY FUND, L.P.
By: Carlson Capital, L.P., its investment manager
By: Asgard Investment Corp. II, its general partner
By:	/s/ Clint D. Carlson
Name:	Clint D. Carlson
Title:	President
CARLSON CAPITAL, L.P.
By: Asgard Investment Corp. II, its general partner
By:	/s/ Clint D. Carlson
Name:	Clint D. Carlson
Title:	President

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ASGARD INVESTMENT CORP. II
By:	/s/ Clint D. Carlson
Name:	Clint D. Carlson
Title:	President
CLINT D. CARLSON
/s/ Clint D. Carlson

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