Sec Form 4 Filing - Yehoshua Tamar @ Slack Technologies, Inc. - 2021-07-21

FORM 4 Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

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, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940

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1. Name and Address of Reporting Person Yehoshua Tamar 2. Issuer Name and Ticker or Trading Symbol Slack Technologies, Inc. [ WORK] 5. Relationship of Reporting Person(s) to Issuer (Check all applicable) _____ Director _____ 10% Owner X __ Officer (give title below) _____ Other (specify below) Chief Product Officer (Last) (First) (Middle) C/O SLACK TECHNOLOGIES, INC., 500 HOWARD STREET 3. Date of Earliest Transaction (MM/DD/YY) 07/21/2021 (Street) SAN FRANCISCO, CA94105 4. If Amendment, Date Original Filed (MM/DD/YY) 6. Individual or Joint/Group Filing (Check Applicable Line) __ X __ Form filed by One Reporting Person _____ Form filed by More than One Reporting Person (City) (State) (Zip)

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned 1.Title of Security (Instr. 3) 2. Transaction Date (MM/DD/YY) 2A. Deemed Execution Date, if any (MM/DD/YY) 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 07/21/2021 U 83,517 ( 1 ) D 0 D

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 (MM/DD/YY) 3A. Deemed Execution Date, if any (MM/DD/YY) 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 (MM/DD/YY) 7. Title and Amount of Underlying Securities (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 of Derivative Security: 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 Restricted Stock Units ( 3 ) 07/21/2021 D 535,476 ( 4 ) ( 5 ) Class B Common Stock 535,476 $ 0 0 D Stock Option (Right to Buy) $ 24.31 07/21/2021 D 94,896 ( 6 ) 04/05/2030 Class A Common Stock 94,896 $ 0 0 D

Reporting Owners Reporting Owner Name / Address Relationships Director 10% Owner Officer Other Yehoshua Tamar C/O SLACK TECHNOLOGIES, INC. 500 HOWARD STREET SAN FRANCISCO, CA94105 Chief Product Officer Signatures /s/ David Schellhase, as Attorney-in-Fact 07/21/2021 Signature of Reporting Person Date

Explanation of Responses:

( 1 )Includes 30,919 shares of Class A common stock subject to restricted stock units ("RSUs") of the Issuer. Pursuant to the the Agreement and Plan of Merger, dated as of December 1, 2020 (the "Merger Agreement"), by and among salesforce.com, inc. ("Salesforce"), Skyline Strategies I Inc., Skyline Strategies II LLC, and the Issuer, at the effective time of the merger (the "Effective Time"), each of the Issuer's RSUs were assumed and converted into an RSU with respect to a number of shares of Salesforce common stock (rounded down to the nearest whole share) determined by multiplying (i) the number of shares of common stock subject to the Issuer RSU immediately prior to the Effective Time by (ii) the "option/RSU conversion ratio" as defined in the definitive proxy statement filed by the Issuer with the SEC on January 29, 2021. The converted RSU will otherwise be subject to the same terms and conditions as were applicable to the Issuer RSU prior to the Effective Time. ( 2 )Pursuant to the Merger Agreement, each share of the Issuer's common stock was tendered in exchange for (i) 0.0776 shares of Salesforce common stock and (ii) $26.79 in cash, together with cash in lieu of any fractional shares of Salesforce common stock. ( 3 )This RSU represents the right to receive shares of Class B common stock. ( 4 )Pursuant to the Merger Agreement, at the Effective Time, each of the Issuer's RSUs were assumed and converted into an RSU with respect to a number of shares of Salesforce common stock (rounded down to the nearest whole share) determined by multiplying (i) the number of shares of common stock subject to the Issuer RSU immediately prior to the Effective Time by (ii) the option/RSU conversion ratio. The converted RSU will otherwise be subject to the same terms and conditions as were applicable to the Issuer RSU prior to the Effective Time. ( 5 )Not applicable. ( 6 )Pursuant to the Merger Agreement, at the Effective Time, each outstanding option was assumed and converted into an option to purchase the number of shares of Salesforce common stock (rounded down to the nearest whole share) determined by multiplying (i) the number of shares of common stock subject to the Issuer option immediately prior to the Effective Time by (ii) the option/RSU conversion ratio, with an exercise price determined by dividing (i) the exercise price of the Issuer option immediately prior to the Effective Time by (ii) the option/RSU conversion ratio. The converted option will otherwise be subject to the same terms and conditions as were applicable to the Issuer option prior to the Effective Time.

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* If the form is filed by more than one reporting person, see Instruction 4(b)(v).

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