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* Sands Capital Ventures Discovery Fund III, L.P. (Last) (First) (Middle) 1000 WILSON BLVD., SUITE 3000 (Street) ARLINGTON VA 22209 (City) (State) (Zip)	2. Date of Event Requiring Statement (Month/Day/Year) 06/30/2021	3. Issuer Name and Ticker or Trading Symbol Acumen Pharmaceuticals, Inc. [ ABOS ]
		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)
	Date Exercisable	Expiration Date	Title	Amount or Number of Shares
Series A-1 Preferred Stock	(1)	(1)	Common Stock	1,124,729	(1)	D(2)(4)
Series B Preferred Stock	(1)	(1)	Common Stock	1,842,346	(1)	D(3)(4)

1. Name and Address of Reporting Person* Sands Capital Ventures Discovery Fund III, L.P. (Last) (First) (Middle) 1000 WILSON BLVD., SUITE 3000 (Street) ARLINGTON VA 22209 (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* Sands Capital Global Venture Fund II, L.P. (Last) (First) (Middle) 1000 WILSON BLVD, SUITE 3000 (Street) ARLINGTON VA 22209 (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* Sands Capital Life Sciences Pulse Fund, LLC (Last) (First) (Middle) 1000 WILSON BLVD, SUITE 3000 (Street) ARLINGTON VA 22209 (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* SANDS FRANK M. (Last) (First) (Middle) 1000 WILSON BLVD, SUITE 3000 (Street) ARLINGTON VA 22209 (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. Each share of Series A-1 Preferred Stock and each share of Series B Preferred Stock will automatically convert into one share of Common Stock of the Issuer upon the closing of the Issuer's initial public offering. The Series A-1 Preferred and the Series B Preferred Stock have no expiration date.

2. Represents Series A-1 Preferred Stock held by Sands Capital Ventures Discovery Fund III, L.P. ("Sands Discovery Fund "). Sands Capital Ventures Discovery Fund III-GP, LLC ("Sands Discovery GP") is the general partner of Sands Discovery Fund. Sands Discovery GP disclaims beneficial ownership of such securities except to the extent of its pecuniary interest therein. Frank M. Sands holds ultimate voting and investment power over these securities and may be deemed to beneficially own the securities.

3. Represents 921,173 shares of Series B Preferred Stock held by Sands Capital Global Venture Fund II, L.P. ("Sands Venture Fund") and 921,173 shares of Series B Preferred Stock held by Sands Capital Life Sciences Pulse Fund, LLC ("Sands Pulse Fund"). Sands Capital Global Venture Fund II-GP, L.P. ("Sands Venture GP L.P.") is the general partner of Sands Venture Fund. Sands Capital Global Venture Discovery Fund II-GP, LLC ("Sands Venture GP LLC") is the general partner of Sands Venture GP L.P. Sands Venture GP L.P. and Sands Venture GP LLC each disclaim beneficial ownership of such securities except to the extent of their relative pecuniary interest therein.

4. Frank M. Sands holds ultimate voting and investment power over securities held by Sands Discovery Fund, Sands Venture Fund and Sands Pulse Fund. Mr. Sands disclaims beneficial ownership of such securities except to the extent of his pecuniary interest therein.

Remarks:

	/s/ Jonathan Goodman, General Counsel of Sands Capital Ventures Discovery Fund III-GP, LLC, the General Partner of Sands Capital Ventures Discovery Fund III, L.P.	06/30/2021
	/s/ Jonathan Goodman, General Counsel of Sands Capital Global Venture Discovery Fund II-GP, LLC, the General Partner of Sands Capital Global Venture Fund II-GP, L.P., the General Partner of Sands Capital Venture Fund II, L.P.	06/30/2021
	/s/ Jonathan Goodman, General Counsel of Sands Capital Life Sciences Pulse Fund, LLC	06/30/2021
	/s/ Frank M. Sands	06/30/2021
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
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