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* Viscuso Michael (Last) (First) (Middle) C/O CARBON BLACK, INC. 1100 WINTER STREET (Street) WALTHAM MA 02451 (City) (State) (Zip)	2. Issuer Name and Ticker or Trading Symbol Carbon Black, Inc. [ CBLK ]	5. Relationship of Reporting Person(s) to Issuer (Check all applicable) Director 10% Owner X Officer (give title below) Other (specify below) Chief Technology Officer
	3. Date of Earliest Transaction (Month/Day/Year) 05/08/2018
	4. If Amendment, Date of Original Filed (Month/Day/Year)	6. Individual or Joint/Group Filing (Check Applicable Line) X Form filed by One Reporting Person 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
Common Stock	05/08/2018		C		263,902	A	(1)	263,902	D
Common Stock	05/08/2018		A		18,750(2)	A	$0	282,652	D
Common Stock	05/08/2018		C		1,056,132	A	(1)	1,056,132	I	By Legion Capital, LLC(3)

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
Series E-1 Convertible Preferred	(1)	05/08/2018		C			527,804	(1)	(1)	Common Stock	263,902	(1)	0	D
Stock Option (right to buy)	(4)	05/08/2018		C			449,841(4)	(4)	03/15/2022	Series E-1 Convertible Preferred Stock	449,841	$0.00	0	D
Stock Option (right to buy)	$0.08	05/08/2018		A		224,920(4)		(4)	03/15/2022	Common Stock	224,920	$0.00	224,920	D
Stock Option (right to buy)	$3.1	05/08/2018		C		68,129(5)		(5)	01/26/2027	Series A Redeemable Preferred Stock	68,129	$0.00	68,129	D
Stock Option (right to buy)	$3.1	05/08/2018		C			68,129(5)	(5)	01/26/2027	Series A Redeemable Preferred Stock	68,129	$0.00	0	D
Stock Option (right to buy)	$7.64	05/08/2018		C		27,645(5)		(5)	01/26/2027	Common Stock	27,645	$0.00	27,645	D
Series E-1 Convertible Preferred	(1)	05/08/2018		C			2,112,265	(1)	(1)	Common Stock	1,056,132	(1)	0	I	By Legion Capital, LLC(3)

Explanation of Responses:

1. Each share of Series E-1 Convertible Preferred Stock was convertible and automatically converted into shares of Common Stock on a 1-for-2 basis upon the closing of the Issuer's initial public offering and has no expiration date.

2. The shares were acquired pursuant to a restricted stock unit award under the Carbon Black 2012 Stock Option and Grant Plan. Each restricted stock unit represents a contingent right to receive one share of Carbon Black, Inc. common stock. The restricted stock unit vests 25% on January 1, 2019, and thereafter in twelve equal quarterly installments beginning June 2, 2019.

3. The shares are held directly by Legion Capital, LLC ("Legion Capital"). Kyrus Holdings, Inc. ("Kyrus Holdings") is an entity that controls Legion Capital. Mr. Viscuso is a member of the board of directors and a stockholder of Kyrus Holdings. Mr. Viscuso disclaims beneficial ownership of all shares except to the extent of his pecuniary interest, if any, therein.

4. Each stock option to buy Series E-1 Convertible Preferred Stock was convertible into and automatically converted into a stock option to buy Common Stock on a 1-for-2 basis upon the closing of the Issuer's initial public offering. This stock option is fully vested.

5. Each stock option to buy Series A Redeemable Preferred Stock became exercisable for a fixed number of shares and automatically converted into a stock option to buy Common Stock on approximately a 0.406-for-1 basis upon the closing of the Issuer's initial public offering. The stock option vested 25% on January 1, 2018 and the remainder vests in equal monthly installments such that the option will be fully vested on January 1, 2021.

	/s/ Eric Pyenson, attorney-in-fact	05/10/2018
	** Signature of Reporting Person	Date
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