[Form 4] BLACKLINE, INC. Insider Trading Activity

Rhea-AI Filing Summary

Thomas Unterman, a director of BlackLine, Inc. (BL), reported multiple sales of Common Stock under a Rule 10b5-1 trading plan adopted on November 21, 2024. The Form 4 lists a sequence of dispositions: 2,730 shares on 05/12/2025 at $55, then 910 shares on 05/20/2025 at $55, 910 shares on 06/20/2025 at $55.23, 885 shares on 07/21/2025 at $56.70, 910 shares on 08/28/2025 at $55, and 910 shares on 09/22/2025 at $55.

Following these transactions the beneficial ownership reported on the form declined in steps from 47,270 shares to 44,565 shares (direct/indirect shown as indirect via ETU Rustic Canyon Trust). The Form 4 was signed by an attorney-in-fact on 09/24/2025.

Positive

• Transactions executed under a Rule 10b5-1 plan, indicating pre-arranged, compliance-oriented trading
• Full transactional detail provided (dates, share amounts, and prices) allowing transparent disclosure

Negative

• Director reduced beneficial holdings across multiple sales, with reported ownership declining from 47,270 to 44,565 shares per line items
• Concentrated set of sales over 2025 which may be viewed by some investors as insider liquidity (no explanation beyond the 10b5-1 plan is provided)

Insights

Securities Analyst

TL;DR: Routine director stock sales executed under a pre-established 10b5-1 plan; reduces reported beneficial holdings modestly.

The filings show scheduled dispositions executed across six dates in 2025 at prices between $55.00 and $56.70 under a Rule 10b5-1 plan adopted November 21, 2024. Such plans are commonly used to avoid insider trading concerns by setting predetermined trade parameters. The total sequence of reported sales reduced reported beneficial ownership from 47,270 shares to 44,565 shares according to the line items shown, and the holdings are disclosed as indirect via ETU Rustic Canyon Trust. For investors, this is a disclosure of insider liquidity rather than new information about company operations or financial performance.

Corporate Governance Expert

TL;DR: Governance-compliant transactions documented; 10b5-1 adoption date is disclosed, supporting procedural compliance.

The Form 4 explicitly states the transactions were effectuated pursuant to a Rule 10b5-1 trading plan adopted on November 21, 2024, and provides transaction dates, share counts, and prices. The signature is provided by an attorney-in-fact on 09/24/2025. From a governance perspective, the disclosure meets standard requirements: relationship to issuer (director) is indicated, and each sale line is reported. No material governance concerns or policy breaches are shown in the text provided.

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^*

Unterman Thomas

(Last) (First) (Middle)

21300 VICTORY BLVD., 12TH FLOOR

(Street)

WOODLAND HILLS CA 91367

(City) (State) (Zip)

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

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

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

3. Date of Earliest Transaction (Month/Day/Year)
05/12/2025

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	05/12/2025		S(1)		2,730	D	$55	47,270	I	ETU Rustic Canyon Trust
Common Stock	05/20/2025		S(1)		910	D	$55	46,360	I	ETU Rustic Canyon Trust
Common Stock	06/20/2025		S(1)		910	D	$55.23	45,450	I	ETU Rustic Canyon Trust
Common Stock	07/21/2025		S(1)		885	D	$56.7	44,565	I	ETU Rustic Canyon Trust
Common Stock	08/28/2025		S(1)		910	D	$55	43,655	I	ETU Rustic Canyon Trust
Common Stock	09/22/2025		S(1)		910	D	$55	42,745	I	ETU Rustic Canyon Trust
Common Stock								58,636	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 transaction reported on this Form 4 was effectuated pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on November 21, 2024.

	/s/ Karole Morgan-Prager, Attorney-in-Fact	09/24/2025
	** 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.

FAQ

What trades did Thomas Unterman report for BL on this Form 4?

He reported six dispositions: 2,730 shares on 05/12/2025 at $55.00; 910 on 05/20/2025 at $55.00; 910 on 06/20/2025 at $55.23; 885 on 07/21/2025 at $56.70; 910 on 08/28/2025 at $55.00; and 910 on 09/22/2025 at $55.00.

Were the sales part of a pre-arranged plan?

Yes. The Form 4 states the transactions were effectuated pursuant to a Rule 10b5-1 trading plan adopted on November 21, 2024.

How did reported beneficial ownership change after the transactions?

Reported beneficial ownership declined in steps

What is the relationship of the reporting person to BL?

Thomas Unterman is reported as a Director of BlackLine, Inc.

When was the Form 4 signed and by whom?

Signed by Karole Morgan-Prager, Attorney-in-Fact on 09/24/2025 according to the signature block.