UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 13G

Under the Securities Exchange Act of 1934

(Amendment No. )*

CARBON BLACK, INC.

(Name of Issuer)

Common Stock, par value $0.001 per share

(Title of Class of Securities)

14081R103

(CUSIP Number)

July 11, 2019

(Date of Event which Requires Filing of this Statement)

Check the appropriate box to designate the rule pursuant to which this Schedule is filed:

[ ] Rule 13d-1(b)

[ X ] 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.

The information required in the remainder of this cover page shall not be deemed to be “filed” for the purpose of Section 18 of the Securities Exchange Act of 1934 (“Act”) or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).

Continued on following pages

Page 1 of 10 Pages

Exhibit Index: Page 9

	SCHEDULE 13G

CUSIP No. 14081R103		Page 2 of 10 Pages

1	NAMES OF REPORTING PERSONS
	LIGHT STREET CAPITAL MANAGEMENT, LLC

2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
	(a)☐
	(b)☐
3	SEC USE ONLY


4	CITIZENSHIP OR PLACE OF ORGANIZATION
	Delaware

NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH		5	SOLE VOTING POWER
			0

		6	SHARED VOTING POWER
			3,729,963

		7	SOLE DISPOSITIVE POWER
			0

		8	SHARED DISPOSITIVE POWER
			3,729,963

9	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
	3,729,963

10	CHECK IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS)
	☐

11	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)
	5.2%

12	TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)
	IA, OO

	SCHEDULE 13G

CUSIP No. 14081R103		Page 3 of 10 Pages

1	NAMES OF REPORTING PERSONS
	GLEN THOMAS KACHER

2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
	(a)☐
	(b)☐
3	SEC USE ONLY


4	CITIZENSHIP OR PLACE OF ORGANIZATION
	United States of America

NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH		5	SOLE VOTING POWER
			0

		6	SHARED VOTING POWER
			3,729,963

		7	SOLE DISPOSITIVE POWER
			0

		8	SHARED DISPOSITIVE POWER
			3,729,963

9	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
	3,729,963

10	CHECK IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS)
	☐

11	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)
	5.2%

12	TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)
	IN, HC

	SCHEDULE 13G

CUSIP No. 14081R103		Page 4 of 10 Pages

1	NAMES OF REPORTING PERSONS
	LIGHT STREET MERCURY MASTER FUND, L.P.

2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
	(a)☐
	(b)☐
3	SEC USE ONLY


4	CITIZENSHIP OR PLACE OF ORGANIZATION
	Cayman Islands

NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH		5	SOLE VOTING POWER
			0

		6	SHARED VOTING POWER
			3,550,000

		7	SOLE DISPOSITIVE POWER
			0

		8	SHARED DISPOSITIVE POWER
			3,550,000

9	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
	3,550,000

10	CHECK IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS)
	☐

11	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)
	4.96%

12	TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)
	OO, PN

Page 5 of 10 Pages

Item 1(a).

Name of Issuer:

Carbon Black, Inc. (the “Issuer”)

Item 1(b).

Address of Issuer’s Principal Executive Offices:

1100 Winter Street, Waltham, Massachusetts 02451

Item 2(a).

Name of Person Filing

This Statement is filed on behalf of each of the following persons (collectively, the “Reporting Persons”)

Light Street Capital Management, LLC (“LSCM”);

ii)

Glen Thomas Kacher (“Mr. Kacher”); and

iii)

Light Street Mercury Master Fund, L.P. (“Mercury”).

This Statement relates to Shares (as defined herein), held for the account of Mercury, an exempted limited partnership in the Cayman Islands, and Light Street Tungsten Master Fund, L.P., an exempted limited partnership in the Cayman Islands (“Tungsten”). LSCM serves as investment adviser and general partner to each of Mercury and Tungsten, and, in such capacities, exercises voting and investment power over the Shares held in the accounts for each of Mercury and Tungsten. Mr. Kacher is the Chief Investment Officer of LSCM.

Item 2(b).

Address of Principal Business Office or, if None, Residence:

The address of the principal business office of each of the Reporting Persons is 525 University Avenue, Suite 300, Palo Alto, CA 94301.

Item 2(c).

Citizenship:

LSCM is a limited liability company incorporated in Delaware;

ii)

Mr. Kacher is a citizen of the United States of America; and

iii)

Mercury is an exempted limited partnership in the Cayman Islands.

Item 2(d).

Title of Class of Securities:

Common Stock, par value $0.001 per share (“Shares”)

Item 2(e).

CUSIP Number:

14081R103

Item 3.

If This Statement is Filed Pursuant to §§240.13d-1(b) or 240.13d-2(b) or (c), Check Whether the Person Filing is a:

This Item 3 is not applicable.

Page 6 of 10 Pages

Item 4.

Ownership:

Item 4(a)

Amount Beneficially Owned:

As of July 11, 2019, each of LSCM and Mr. Kacher may have been deemed the beneficial owner of 3,779,963 Shares. This amount consisted of: (A) 3,600,000 Shares held for the account of Mercury; and (B) 179,963 Shares held for the account of Tungsten. As of July 19, 2019, each of LSCM and Mr. Kacher may be deemed the beneficial owner of 3,729,963 Shares. This amount consists of: (A) 3,550,000 Shares held for the account of Mercury; and (B) 179,963 Shares held for the account of Tungsten.

Item 4(b)

Percent of Class:

As of July 11, 2019, each of LSCM and Mr. Kacher may have been deemed the beneficial owner of approximately 5.3% of Shares outstanding, including approximately 5.03% of Shares outstanding held for the account of Mercury. As of July 19, 2019, each of LSCM and Mr. Kacher may be deemed the beneficial owner of approximately 5.2% of Shares outstanding, including approximately 4.96% of Shares outstanding held for the account of Mercury. (These percentages are based on 71,569,406 Shares outstanding as of April 30, 2019, as reported in the Form 10-Q filed by the Issuer with the Securities and Exchange Commission on May 2, 2019.)

Item 4(c)

Number of Shares as to which such person has:

LSCM and Mr. Kacher:

(i) Sole power to vote or direct the vote:	0
(ii) Shared power to vote or direct the vote:	3,729,963
(iii) Sole power to dispose or direct the disposition of:	0
(iv) Shared power to dispose or direct the disposition of:	3,729,963

Mercury:

(i) Sole power to vote or direct the vote:	0
(ii) Shared power to vote or direct the vote:	3,550,000
(iii) Sole power to dispose or direct the disposition of:	0
(iv) Shared power to dispose or direct the disposition of:	3,550,000

Item 5.

Ownership of Five Percent or Less of a Class:

As of July 19, 2019, Mercury has ceased to be the beneficial owner of more than 5% of the Shares.

Item 6.

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

See disclosure in Items 2 and 4 hereof.

Item 7.

Identification and Classification of the Subsidiary Which Acquired the Security Being Reported on By the Parent Holding Company or Control Person:

See disclosure in Item 2 hereof.

Page 7 of 10 Pages

Item 8.

Identification and Classification of Members of the Group:

This Item 8 is not applicable.

Item 9.

Notice of Dissolution of Group:

This Item 9 is not applicable.

Item 10.

Certification:

By signing below I certify that, to the best of my knowledge and belief, the securities referred to above were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities and were not acquired and are not held in connection with or as a participant in any transaction having that purpose or effect, other than activities solely in connection with a nomination under §240.14a-11.

Page 8 of 10 Pages

SIGNATURE

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

	Light Street Capital Management, LLC

	By:	/s/ Theo J. Robins
		Theo J. Robins
		Chief Compliance Officer

	Glen Thomas Kacher

	By:	/s/ Glen Thomas Kacher

	Light Street Mercury Master Fund, L.P.

	By:	Light Street Capital Management, LLC

	By:	/s/ Theo J. Robins
		Theo J. Robins
		Chief Compliance Officer

July 22, 2019

Page 9 of 10 Pages

EXHIBIT INDEX

Ex.

Page No.

Joint Filing Agreement

Page 10 of 10 Pages

EXHIBIT A

JOINT FILING AGREEMENT

The undersigned hereby agree that the statement on Schedule 13G with respect to the Common Stock of Carbon Black, Inc. dated as of July 22, 2019 is, and any amendments thereto (including amendments on Schedule 13D) signed by each of the undersigned shall be, filed on behalf of each of us pursuant to and in accordance with the provisions of Rule 13d-1(k) under the Securities Exchange Act of 1934, as amended.

	Light Street Capital Management, LLC

	By:	/s/ Theo J. Robins
		Theo J. Robins
		Chief Compliance Officer

	Glen Thomas Kacher

	By:	/s/ Glen Thomas Kacher

	Light Street Mercury Master Fund, L.P.

	By:	Light Street Capital Management, LLC

	By:	/s/ Theo J. Robins
		Theo J. Robins
		Chief Compliance Officer

July 22, 2019

Carbon Black, Inc. SC 13G