Du Ying Exercises Options at $0.60, Sells 100k ZLAB ADSs Under 10b5-1

Rhea-AI Filing Summary

Zai Lab director and CEO Du Ying reported exercising and selling American Depositary Shares (ADSs) in matched transactions. On 08/08/2025 and 08/11/2025 she exercised two separate blocks of 50,000 ADS-equivalent stock options each at an exercise price of $0.60 per ADS and contemporaneously sold the same amounts under a pre-existing Rule 10b5-1 trading plan adopted on November 20, 2024. The reported weighted-average sale prices were $34.7431 and $34.6363, with disclosed price ranges for each sale. Each ADS represents 10 ordinary shares. Following the reported transactions the Form 4 shows beneficial ownership of 536,962 ADSs and remaining derivative holdings of 96,387 stock options. The Form notes the options had fully vested as of October 22, 2020 and offers to provide per-price sale details to regulators or security holders.

Positive

• Transactions were executed under a Rule 10b5-1 trading plan adopted on November 20, 2024, indicating pre-arranged sales
• Options exercised at $0.60 per ADS and sold at weighted-average prices around $34.74, realizing a substantial spread per ADS based on disclosed prices

Negative

• 100,000 ADSs were sold across the two reported transactions, reducing reported beneficial ownership to 536,962 ADSs
• Remaining derivative holdings decreased to 96,387 stock options after the reported exercises

Insights

Securities Analyst

TL;DR: Insider exercised low-strike options and sold equal ADS blocks under a 10b5-1 plan, realizing proceeds near $34.7 per ADS; ownership modestly reduced.

The filings show two matched exercise-and-sale events: 50,000 ADSs exercised at $0.60 and sold at a weighted average of $34.7431 on 08/08/2025, and a further 50,000 exercised at $0.60 and sold at a weighted average of $34.6363 on 08/11/2025. Transactions were executed pursuant to a 10b5-1 plan, which generally indicates preplanned sales rather than opportunistic trading. The filing discloses remaining beneficial ADS ownership of 536,962 and derivative holdings of 96,387 options. From a securities perspective this is a routine realization of gains from vested options, reported in compliance with Section 16.

Corporate Governance Expert

TL;DR: Use of a documented 10b5-1 plan and clear disclosure of exercise, sale prices, and vesting supports governance and reporting transparency.

The Form 4 discloses that the trades were effected under a Rule 10b5-1 trading plan adopted on November 20, 2024, and that the stock options had fully vested on October 22, 2020. The filing provides weighted-average sale prices, price ranges, and offers further per-price details to the SEC, issuer, or holders, which reflects a high level of disclosure. The signature by an attorney-in-fact is noted on the form, indicating proper execution of reporting formalities. Governance implications are procedural rather than material market events based on the facts disclosed.

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^*

Du Ying

(Last) (First) (Middle)

C/O ZAI LAB LIMITED

314 MAIN STREET, 4TH FLOOR, SUITE 100

(Street)

CAMBRIDGE MA 02142

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
Zai Lab Ltd [ ZLAB ]

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

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

3. Date of Earliest Transaction (Month/Day/Year)
08/08/2025

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
American Depositary Shares(1)	08/08/2025		M		50,000	A	$0.6	586,962	D
American Depositary Shares(1)	08/08/2025		S(2)		50,000	D	$34.7431(3)	536,962	D
American Depositary Shares(1)	08/11/2025		M		50,000	A	$0.6	586,962	D
American Depositary Shares(1)	08/11/2025		S(2)		50,000	D	$34.6363(4)	536,962	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
Stock Options (Right to Buy)	$0.6	08/08/2025		M			50,000	(5)	10/22/2025	American Depositary Shares(1)	50,000	$0	146,387	D
Stock Options (Right to Buy)	$0.6	08/11/2025		M			50,000	(5)	10/22/2025	American Depositary Shares(1)	50,000	$0	96,387	D

Explanation of Responses:

1. Each American Depositary Share ("ADS") represents ten Ordinary Shares of the issuer. Our ADSs and Ordinary Shares are fully fungible. For purposes of this Form 4, we are reporting this in terms of ADSs.

2. The transactions reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on November 20, 2024.

3. Reflects a weighted average sale price of $34.7431 per share, at prices ranging from $34.095 to $35.00 per share. The Reporting Person will provide, upon request by the staff of the Securities and Exchange Commission, the Issuer, or a security holder of the Issuer, full information regarding the number of shares sold at each separate price.

4. Reflects a weighted average sale price of $34.6363 per share, at prices ranging from $34.22 to $35.19 per share. The Reporting Person will provide, upon request by the staff of the Securities and Exchange Commission, the Issuer, or a security holder of the Issuer, full information regarding the number of shares sold at each separate price.

5. The Stock Options fully vested as of October 22, 2020.

	/s/ Bruce Blefeld, Attorney-in-Fact	08/12/2025
	** 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 insider transactions did Du Ying report for ZLAB?

Du Ying reported exercising two blocks of 50,000 ADS-equivalent stock options and selling the same amounts on 08/08/2025 and 08/11/2025 under a 10b5-1 plan.

What were the exercise and sale prices reported in the ZLAB Form 4?

The exercise price was $0.60 per ADS; weighted-average sale prices were $34.7431 (08/08/2025) and $34.6363 (08/11/2025), with disclosed price ranges for each sale.

How many ADSs does Du Ying beneficially own after these transactions?

The Form 4 reports 536,962 ADSs beneficially owned following the reported transactions.

Were the stock options vested before exercise?

Yes. The filing states the stock options fully vested as of October 22, 2020.

Was a trading plan used for the sales in the ZLAB filing?

Yes. The transactions were effected pursuant to a Rule 10b5-1 trading plan adopted on November 20, 2024.