CBIO CMO sells 1,219 shares for tax withholding

CRESCENT BIOPHARMA, INC.

Rhea-AI Filing Summary

CRESCENT BIOPHARMA, INC. Chief Medical Officer Ellie Eunkyung Im reported an open-market sale of 1,219 Ordinary Shares at a weighted average price of $17.99 per share. The footnotes explain these shares were automatically sold to satisfy tax withholding obligations tied to the vesting of restricted stock units.

The sales were executed under a pre-arranged Rule 10b5-1 instruction adopted on February 25, 2026, and were intended solely to cover taxes from the RSU settlement. After this transaction, the reporting person directly holds 22,069 Ordinary Shares.

Insider Trade Summary 10b5-1

Net Seller: 1,219 shares

Net Sell 1 txn

Insider Im Ellie Eunkyung

Role Chief Medical Officer

Sold 1,219 shs ($22K)

Type	Security	Shares	Price	Value
Sale	Ordinary Shares	1,219	$17.99	$22K

Holdings After Transaction: Ordinary Shares — 22,069 shares (Direct)

Footnotes (2)

1. F1. Represents shares automatically sold by the Reporting Person to satisfy tax withholding obligations in connection with the settlement of restricted stock units granted to the Reporting Person on December 15, 2025. The sales reported in this Form 4 were effected pursuant to a Rule 10b5-1 instruction adopted by the Reporting Person on February 25, 2026, solely with the intent to cover taxes in connection with the vesting of the restricted stock units.
2. F2. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $16.88 to $18.86, inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price at which the transactions were effected.

Key Figures

Shares sold: 1,219 shares Weighted average sale price: $17.99 per share Sale price range: $16.88–$18.86 per share +3 more

6 metrics

Shares sold 1,219 shares Ordinary Shares sold on June 22, 2026

Weighted average sale price $17.99 per share Open-market sale to cover tax withholding

Sale price range $16.88–$18.86 per share Multiple transactions included in this Form 4

Shares owned after transaction 22,069 shares Direct ownership following tax-related sale

RSU grant date December 15, 2025 Restricted stock units that triggered tax withholding

Rule 10b5-1 adoption date February 25, 2026 Instruction governing tax-related share sales

Key Terms

restricted stock units, tax withholding obligations, Rule 10b5-1 instruction, weighted average price

4 terms

restricted stock units financial

"in connection with the settlement of restricted stock units granted to the Reporting Person"

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.

tax withholding obligations financial

"shares automatically sold by the Reporting Person to satisfy tax withholding obligations"

Rule 10b5-1 instruction regulatory

"sales reported in this Form 4 were effected pursuant to a Rule 10b5-1 instruction"

weighted average price financial

"The price reported in Column 4 is a weighted average price."

Weighted average price is the average price of a security where each trade or component is counted according to its size, so bigger trades pull the average more than smaller ones. Think of it like calculating the average cost of a grocery haul where items you bought more of have greater influence on the final per-item cost. Investors use it to understand the true average price paid or received, judge execution quality, and compare trading performance against market movement.

FAQ

AI-generated questions and answers. How Rhea-AI works. Not financial advice.

What insider transaction did CBIO’s Chief Medical Officer report on this Form 4?

The Chief Medical Officer, Ellie Eunkyung Im, reported selling 1,219 Ordinary Shares of CRESCENT BIOPHARMA at a weighted average price of $17.99 per share. This transaction is classified as an open-market sale of non-derivative securities and was linked to restricted stock unit vesting.

Why were Ellie Eunkyung Im’s CBIO shares sold in this transaction?

The shares were sold automatically to cover tax withholding obligations arising from the settlement of restricted stock units granted on December 15, 2025. The filing notes the sole intent of the sales was to satisfy taxes related to RSU vesting, rather than a discretionary portfolio decision.

Was the CBIO insider sale by the Chief Medical Officer pre-planned?

Yes. The filing states the sales were effected pursuant to a Rule 10b5-1 instruction adopted on February 25, 2026. Such pre-planned instructions schedule trades in advance, helping separate routine tax or liquidity events from timing-based trading decisions.

How many CBIO shares does the Chief Medical Officer hold after this transaction?

Following the reported sale, Ellie Eunkyung Im directly holds 22,069 Ordinary Shares of CRESCENT BIOPHARMA. This figure reflects her remaining direct ownership after the 1,219 shares were sold to cover tax withholding obligations from restricted stock unit settlement.

What price range did the CBIO shares sell for in this Form 4 transaction?

The weighted average sale price was reported as $17.99 per share. Footnotes explain the 1,219 shares were sold in multiple trades at prices ranging from $16.88 to $18.86, and detailed trade data is available from the reporting person upon request.

What type of CBIO security was involved in the Chief Medical Officer’s sale?

The transaction involved Ordinary Shares of CRESCENT BIOPHARMA, not derivative securities. These shares were sold in open-market transactions specifically to satisfy tax withholding obligations tied to previously granted restricted stock units that had recently vested.

AI-generated analysis. How Rhea-AI works. Not financial advice.

Form 4 Insider Transactions: What Each Field Means →

See more from StockTitan in Google Search and AI answers. Adds StockTitan as a preferred source · opens Google

Add on Google Not now

Accepted by SEC EDGAR 06/23/2026 - 04:02 PM EDT Learn about SEC filing dates

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).

X

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^*

Im Ellie Eunkyung

(Last) (First) (Middle)

C/O CRESCENT BIOPHARMA, INC.

300 FIFTH AVENUE

(Street)

WALTHAM MASSACHUSETTS 02451

(City) (State) (Zip)

UNITED STATES

(Country)

2. Issuer Name and Ticker or Trading Symbol
CRESCENT BIOPHARMA, INC. [ CBIO ]

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

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

2a. Foreign Trading Symbol

3. Date of Earliest Transaction (Month/Day/Year)
06/22/2026

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
Ordinary Shares	06/22/2026		S		1,219(1)	D	$17.99(2)	22,069	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. Represents shares automatically sold by the Reporting Person to satisfy tax withholding obligations in connection with the settlement of restricted stock units granted to the Reporting Person on December 15, 2025. The sales reported in this Form 4 were effected pursuant to a Rule 10b5-1 instruction adopted by the Reporting Person on February 25, 2026, solely with the intent to cover taxes in connection with the vesting of the restricted stock units.

2. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $16.88 to $18.86, inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price at which the transactions were effected.

Remarks:

	/s/ Barbara Bispham, as attorney-in-fact for Ellie Im	06/23/2026
	** 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)