Was Neil Lerner’s CMPX share grant an open-market purchase or a compensation award?

The 15,000 CMPX shares reported by Neil Lerner were a grant or award acquisition, not an open-market purchase. The Form 4 uses transaction code A, indicating a grant, at a reported price of $1.89 per share as part of his compensation.

How significant is Neil Lerner’s 15,000-share CMPX grant compared with his total holdings?

The 15,000-share grant is a relatively small addition compared with Neil Lerner’s total 397,500 CMPX shares after the transaction. This indicates a routine compensation-related award rather than a large shift in his overall ownership position in Compass Therapeutics.

Compass Therapeutics (CMPX) CAO receives 15,000-share equity grant

Filing Impact

(Neutral)

Filing Sentiment

(Neutral)

Form Type

Rhea-AI Filing Summary

Lerner Neil reported acquisition or exercise transactions in this Form 4 filing.

Compass Therapeutics, Inc. Chief Accounting Officer Neil Lerner received a grant of 15,000 shares of common stock at $1.89 per share on April 29, 2026, increasing his direct holdings to 397,500 shares. A footnote notes that 62,500 of these shares are unvested restricted stock units granted on January 2, 2026, which vest in four equal annual installments starting January 2, 2027 under service-based conditions.

Insider Trade Summary

1 transaction reported

Mixed 1 txn

Insider Lerner Neil

Role Chief Accounting Officer

Type	Security	Shares	Price	Value
Grant/Award	Common Stock	15,000	$1.89	$28K

Holdings After Transaction: Common Stock — 397,500 shares (Direct, null)

Footnotes (1)

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Key Figures

Shares granted: 15,000 shares Grant price: $1.89 per share Total holdings after grant: 397,500 shares +2 more

5 metrics

Shares granted 15,000 shares Common stock grant to CAO on April 29, 2026

Grant price $1.89 per share Reported transaction price for awarded shares

Total holdings after grant 397,500 shares Directly held Compass Therapeutics common stock

Unvested RSUs 62,500 units Restricted stock units granted January 2, 2026

RSU vesting schedule 4 equal annual installments First installment vests January 2, 2027

Key Terms

restricted stock units, RSU, service-based vesting conditions, transaction code A

4 terms

restricted stock units financial

"62,500 of the shares represents unvested restricted stock units ("RSU") granted on January 2, 2026."

Restricted stock units are a type of company reward where employees are promised shares of stock, but they only fully own these shares after meeting certain conditions, like staying with the company for a set time. They matter because they can become valuable assets and are often used to motivate employees to help the company succeed.

RSU financial

"62,500 of the shares represents unvested restricted stock units ("RSU") granted on January 2, 2026."

Restricted stock units (RSUs) are a form of company shares given to employees as part of their compensation, usually with certain restrictions or conditions, such as remaining with the company for a set period. When these restrictions lift, employees receive actual shares that they can sell or hold. For investors, RSUs can impact a company's stock supply and reflect the company's commitment to attracting and retaining talent.

service-based vesting conditions financial

"The award is subject to service-based vesting conditions and vests in four equal annual installments"

transaction code A financial

"transaction_code": "A","transaction_code_description": "Grant, award, or other acquisition""

Form 4 Insider Transactions: What Each Field Means →

04/29/2026 - 04:58 PM

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).

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^*

Lerner Neil

(Last)

(First)

(Middle)

C/O COMPASS THERAPEUTICS, INC.

80 GUEST STREET, SUITE 601

(Street)

BOSTON

MASSACHUSETTS

02135

(City)

(State)

(Zip)

UNITED STATES

(Country)

2. Issuer Name and Ticker or Trading Symbol
Compass Therapeutics, Inc. [ CMPX ]

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)
04/29/2026

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)
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	Code	V	Amount	(A) or (D)	Price		6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
Common Stock	04/29/2026		A		15,000	A	$1.89	397,500⁽¹⁾	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)
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)	Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares	8. Price of Derivative Security (Instr. 5)		10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)

Explanation of Responses:

1. 62,500 of the shares represents unvested restricted stock units ("RSU") granted on January 2, 2026. Each RSU represents a contingent right to receive one share of common stock. The award is subject to service-based vesting conditions and vests in four equal annual installments, with the first installment vested on January 2, 2027.

	/s/ Neil Lerner	04/29/2026
	** 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.
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.
* Form 4: SEC 1474 (03-26)

Source: View Original Filing on SEC EDGAR

FAQ

What insider transaction did CMPX Chief Accounting Officer Neil Lerner report?

Neil Lerner reported receiving 15,000 shares of Compass Therapeutics common stock as a grant. The shares were valued at $1.89 each, reflecting a compensation award rather than an open-market purchase, and increased his directly held stake to 397,500 shares.

How many Compass Therapeutics shares does Neil Lerner hold after this Form 4 transaction?

After the reported grant, Neil Lerner directly holds 397,500 shares of Compass Therapeutics common stock. This total includes both fully vested shares and 62,500 unvested restricted stock units that are scheduled to vest in future years, subject to service-based conditions.

What are the terms of Neil Lerner’s unvested CMPX restricted stock units?

The filing states 62,500 shares represent unvested restricted stock units granted on January 2, 2026. Each RSU equals one share of common stock and vests in four equal annual installments, beginning January 2, 2027, contingent on meeting service-based vesting conditions.