GLTO Galecto Inc

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.

 NAMES OF REPORTING PERSONS

 I.R.S. IDENTIFICATION NO. OF ABOVE PERSONS (ENTITIES ONLY)

 Sunstone Life Science Ventures Fund III K/S

 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP

 (a) ☐  (b) ☒

 SEC USE ONLY

 CITIZENSHIP OR PLACE OF ORGANIZATION

 Denmark

NUMBER OF

SHARES  BENEFICIALLY 

OWNED BY

EACH

REPORTING

PERSON

WITH

 SOLE VOTING POWER

 1,475,802*

 SHARED VOTING POWER

 0

 SOLE DISPOSITIVE POWER

 1,475,802*

 SHARED DISPOSITIVE POWER

 0

 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

 1,475,802*

 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES

 ☐

 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9

 5.8%*

 TYPE OF REPORTING PERSON

 PN

Represents shares of Common Stock, par value $0.00001 per share (“Common Stock”) held by Sunstone Life Science Ventures Fund III K/S (“Sunstone Fund III”). Sunstone LSV General Partner III ApS (“Sunstone LSV GP III”) is the general partner of Sunstone Fund III and may be deemed to have voting and dispositive power with respect to the shares held by Sunstone Fund III. Sunstone Life Science Ventures A/S is the owner of Sunstone LSV GP III and may be deemed to have voting and dispositive power with respect to the shares held by Sunstone Fund III. The percent of class was calculated based upon 25,261,832 shares of Common Stock of the Issuer outstanding as of March 25, 2021, as reported in the Issuer’s annual report on Form 10-K filed with the Securities and Exchange Commission on March 29, 2021.

 NAMES OF REPORTING PERSONS

 I.R.S. IDENTIFICATION NO. OF ABOVE PERSONS (ENTITIES ONLY)

 Sunstone LSV General Partner III ApS

 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP

 (a) ☐  (b) ☒

 SEC USE ONLY

 CITIZENSHIP OR PLACE OF ORGANIZATION

 Denmark

NUMBER OF

SHARES  BENEFICIALLY 

OWNED BY

EACH

REPORTING

PERSON

WITH

 SOLE VOTING POWER

 1,475,802*

 SHARED VOTING POWER

 0

 SOLE DISPOSITIVE POWER

 1,475,802*

 SHARED DISPOSITIVE POWER

 0

 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

 1,475,802*

 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES

 ☐

 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9

 5.8%*

 TYPE OF REPORTING PERSON

 OO

Represents shares of Common Stock held by Sunstone Fund III. Sunstone LSV GP III is the general partner of Sunstone Fund III and may be deemed to have voting and dispositive power with respect to the shares held by Sunstone Fund III. Sunstone Life Science Ventures A/S is the owner of Sunstone LSV GP III and may be deemed to have voting and dispositive power with respect to the shares held by Sunstone Fund III. The percent of class was calculated based upon 25,261,832 shares of Common Stock of the Issuer outstanding as of March 25, 2021, as reported in the Issuer’s annual report on Form 10-K filed with the Securities and Exchange Commission on March 29, 2021.

 NAMES OF REPORTING PERSONS

 I.R.S. IDENTIFICATION NO. OF ABOVE PERSONS (ENTITIES ONLY)

 Sunstone Life Science Ventures A/S

 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP

 (a) ☐  (b) ☒

 SEC USE ONLY

 CITIZENSHIP OR PLACE OF ORGANIZATION

 Denmark

NUMBER OF

SHARES  BENEFICIALLY 

OWNED BY

EACH

REPORTING

PERSON

WITH

 SOLE VOTING POWER

 1,475,802*

 SHARED VOTING POWER

 0

 SOLE DISPOSITIVE POWER

 1,475,802*

 SHARED DISPOSITIVE POWER

 0

 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

 1,475,802*

 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES

 ☐

 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9

 5.8%*

 TYPE OF REPORTING PERSON

 OO

Represents shares of Common Stock held by Sunstone Fund III. Sunstone LSV GP III is the general partner of Sunstone Fund III and may be deemed to have voting and dispositive power with respect to the shares held by Sunstone Fund III. Sunstone Life Science Ventures A/S is the owner of Sunstone LSV GP III and may be deemed to have voting and dispositive power with respect to the shares held by Sunstone Fund III. The percent of class was calculated based upon 25,261,832 shares of Common Stock of the Issuer outstanding as of March 25, 2021, as reported in the Issuer’s annual report on Form 10-K filed with the Securities and Exchange Commission on March 29, 2021.

Name of Issuer:

Address of Issuer’s Principal Executive Offices:

Name of Person Filing:

Name of Persons Filing; Address; Citizenship

Sunstone Life Science Ventures Fund III K/S, a Danish limited partnership;

Sunstone LSV General Partner III ApS, a Danish private limited company. Sunstone LSV General Partner III ApS is the general partner of Sunstone Life Science Ventures Fund III K/S; and

Sunstone Life Science Ventures A/S, a Danish public limited liability company. Sunstone Life Science Ventures A/S is the owner of Sunstone LSV General Partner III ApS.

Title of Class of Securities:

CUSIP Number:

Not applicable.

Ownership.

Ownership of Five Percent or Less of a Class.

Ownership of More than Five Percent on Behalf of Another Person.

Identification and Classification of the Subsidiary Which Acquired the Security Being Reported on by the Parent Holding Company.

Identification and Classification of Members of the Group.

Notice of Dissolution of Group.

Certification.

Exhibit 99.1

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