[Form 4] BLACKLINE, INC. Insider Trading Activity

Rhea-AI Filing Summary

BLACKLINE, INC. Chief Accounting Officer Michelle D. Stalick reported routine share dispositions tied to tax withholding rather than market sales. On May 20, 2026, a total of 871 shares of common stock were withheld at $30.84 per share to cover tax liabilities from vesting restricted stock units. Following these transactions, she directly held 37,871 shares of common stock. A footnote also states that her holdings include 459 shares acquired on May 8, 2026 through the company’s Employee Stock Purchase Plan in an exempt transaction.

Insider Trade Summary

4 transactions reported

Mixed 4 txns

Insider Stalick Michelle D

Role Chief Accounting Officer

Type	Security	Shares	Price	Value
Tax Withholding	Common Stock	143	$30.84	$4K
Tax Withholding	Common Stock	161	$30.84	$5K
Tax Withholding	Common Stock	266	$30.84	$8K
Tax Withholding	Common Stock	301	$30.84	$9K

Holdings After Transaction: Common Stock — 37,871 shares (Direct, null)

Footnotes (1)

1. The reported shares were withheld to cover the Reporting Person's tax liability in connection with the vesting of restricted stock units. Includes 459 shares acquired on May 8, 2026, through the Issuer's Employee Stock Purchase Plan in a transaction that was exempt under both Rule 16b-3(d) and Rule 16b-3(c).

Form 4 Insider Transactions: What Each Field Means →

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
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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).

Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

1. Name and Address of Reporting Person^*

Stalick Michelle D

(Last) (First) (Middle)

21300 VICTORY BLVD., 12TH FLOOR

(Street)

WOODLAND HILLS CALIFORNIA 91367

(City) (State) (Zip)

UNITED STATES

(Country)

2. Issuer Name and Ticker or Trading Symbol
BLACKLINE, INC. [ BL ]

5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

	Director		10% Owner
X	Officer (give title below)		Other (specify below)
	Chief Accounting Officer

2a. Foreign Trading Symbol

3. Date of Earliest Transaction (Month/Day/Year)
05/20/2026

6. Individual or Joint/Group Filing (Check Applicable Line)

X	Form filed by One Reporting Person
	Form filed by More than One Reporting Person

4. If Amendment, Date of Original Filed (Month/Day/Year)

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	05/20/2026		F		143(1)	D	$30.84	37,871	D
Common Stock	05/20/2026		F		161(1)	D	$30.84	37,710	D
Common Stock	05/20/2026		F		266(1)	D	$30.84	37,444	D
Common Stock	05/20/2026		F		301(1)	D	$30.84	37,143(2)	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 (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

Explanation of Responses:

1. The reported shares were withheld to cover the Reporting Person's tax liability in connection with the vesting of restricted stock units.

2. Includes 459 shares acquired on May 8, 2026, through the Issuer's Employee Stock Purchase Plan in a transaction that was exempt under both Rule 16b-3(d) and Rule 16b-3(c).

	/s/ Karole Morgan-Prager, Attorney-in-Fact	05/21/2026
	** 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.
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* Form 4: SEC 1474 (03-26)