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* Andreessen Marc L (Last) (First) (Middle) 2865 SAND HILL ROAD SUITE 101 (Street) MENLO PARK CA 94025 (City) (State) (Zip)	2. Issuer Name and Ticker or Trading Symbol Slack Technologies, Inc. [ WORK ]	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) 01/08/2020
	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
Class A Common Stock	01/08/2020		S		60,536	D	$24.13(1)	0	I	By AH Capital Management, L.L.C.(2)
Class A Common Stock								9,814,412	I	By Andreessen Horowitz Fund I, L.P.(3)(4)
Class A Common Stock								3,816,419	I	By AH Parallel Fund IV, L.P.(5)(6)
Class A Common Stock								1,413,143	I	By Trust(7)
Class A Common Stock								1,693,391	I	By Trust(8)

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

1. Name and Address of Reporting Person* Andreessen Marc L (Last) (First) (Middle) 2865 SAND HILL ROAD SUITE 101 (Street) MENLO PARK CA 94025 (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* HOROWITZ BENJAMIN A (Last) (First) (Middle) 2865 SAND HILL ROAD SUITE 101 (Street) MENLO PARK CA 94025 (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. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $24.13 to $24.135. The Reporting Persons undertake to provide to the Issuer, any security holder of the Issuer or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.

2. The shares are held of record by AH Capital Management, L.L.C. The members of AH Capital Management, L.L.C. are Marc Andreessen and Ben Horowitz, who share voting and dispositive power with respect to the shares held by AH Capital Management, L.L.C. Each of the Reporting Persons disclaims the existence of a "group" and disclaims beneficial ownership of these securities except to the extent of its pecuniary interest therein, and the inclusion of these securities in this report shall not be deemed an admission of beneficial ownership of the reported securities for purposes of Section 16 or for any other purpose.

3. These shares are held of record by Andreessen Horowitz Fund I, L.P., as nominee for Andreessen Horowitz Fund I, L.P., Andreessen Horowitz Fund I-A, L.P. and Andreessen Horowitz Fund I-B, L.P. (collectively, the "AH Fund I Entities"). AH Equity Partners I, L.L.C. ("AH EP I"), the general partner of the AH Fund I Entities, has sole voting and dispositive power with regard to the shares held by the AH Fund I Entities. The managing members of AH EP I are Marc Andreessen and Ben Horowitz. Marc Andreessen and Ben Horowitz share voting and dispositive power with respect to the shares held by the AH Fund I Entities.

4. (Continued from Footnote 3) Each of the Reporting Persons disclaims the existence of a "group" and disclaims beneficial ownership of the securities held by the AH Fund I Entities (and this report shall not be deemed an admission that any such person is the beneficial owner of such securities), except to the extent of its pecuniary interest, if any, in the securities by virtue of its interest in the AH Fund I Entities.

5. These shares are held of record by AH Parallel Fund IV, L.P., for itself and as nominee for AH Parallel Fund IV-A, L.P., AH Parallel Fund IV-B, L.P., and AH Parallel Fund IV-Q, L.P. (collectively the "AH Parallel Fund IV Entities"). AH Equity Partners IV (Parallel), L.L.C. ("AH EP IV Parallel"), the general partner of the AH Parallel Fund IV Entities, has sole voting and dispositive power with regard to the shares held by the AH Parallel Fund IV Entities. The managing members of AH EP IV Parallel are Marc Andreessen and Ben Horowitz. Marc Andreessen and Ben Horowitz share voting and dispositive power with respect to the shares held by the AH Parallel Fund IV Entities.

6. (Continued from Footnote 5) Each of the Reporting Persons disclaims the existence of a "group" and disclaims beneficial ownership of the securities held by the AH Parallel Fund IV Entities (and this report shall not be deemed an admission that any such person is the beneficial owner of such securities), except to the extent of its pecuniary interest, if any, in the securities by virtue of its interest in the AH Parallel Fund IV Entities.

7. The shares are held of record by the LAMA Community Trust of which Marc Andreessen and his spouse are trustees. Each of the Reporting Persons disclaims the existence of a "group" and, other than Marc Andreessen, disclaims beneficial ownership of these securities, and the inclusion of these securities in this report shall not be deemed an admission of beneficial ownership of the reported securities for purposes of Section 16 or for any other purpose.

8. The shares are held of record by a family trust for which Ben Horowitz is a trustee. Each of the Reporting Persons disclaims the existence of a "group" and, other than Ben Horowitz, disclaims beneficial ownership of these securities, and the inclusion of these securities in this report shall not be deemed an admission of beneficial ownership of the reported securities for purposes of Section 16 or for any other purpose.

Remarks:

	Marc Andreessen /s/ Scott Kupor Scott Kupor, attorney-in-fact of Marc Andreessen	01/10/2020
	Ben Horowitz /s/ Scott Kupor Scott Kupor, attorney-in-fact of Ben Horowitz	01/10/2020
	** 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).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.