[Form 4] Zai Lab Limited American Insider Trading Activity

Rhea-AI Filing Summary

Key Form 4 details for Zai Lab Ltd (ZLAB): On 25 June 2025, Chairperson & CEO Ying Du received 58,800 American Depositary Shares (ADS) upon the vesting of previously granted Restricted Share Units (RSUs). Each ADS represents ten ordinary shares. The conversion was reported under transaction code “M,” indicating a delivery of shares without cash consideration.

On 26 June 2025 the executive executed an automatic sale (code “S”) of 23,669 ADS at US $36.132 per ADS to satisfy tax-withholding obligations triggered by the vesting event. After both transactions, Du’s direct beneficial ownership stands at 514,982 ADS.

Net effect: the CEO’s holdings increased by 35,131 ADS relative to the amount immediately prior to the RSU vesting, reinforcing management’s equity alignment while acknowledging routine tax-related disposals. No derivative positions remain in connection with this RSU tranche.

The RSUs follow a four-year vesting schedule that began on 25 June 2023; future anniversaries may lead to similar withhold-to-cover sales. Investors typically view net ownership increases as a positive governance signal, although periodic sales could add modest near-term share supply.

Insights

Securities Analyst

TL;DR Net 35 k ADS increase; sale only for taxes—overall neutral, mild governance positive.

The filing shows a routine RSU vest. The automatic tax sale realises roughly US $0.86 m but is not discretionary. Because Du’s aggregate stake rose to 514,982 ADS, the transaction suggests continuing commitment rather than profit-taking. No material cash outlay or large open-market disposal occurred, so market impact should be limited. I view the event as governance-neutral, with a slight positive tilt due to higher insider ownership.

Corporate Governance Specialist

TL;DR Standard 10b5-1 tax sale; insider retains sizable stake—no red flags detected.

Form 4 indicates compliance with Section 16 reporting and Rule 10b5-1 safeguards. The mix of code “M” (vest) and code “S” (sale) is typical for executive compensation plans. Retained ownership of over half a million ADS aligns CEO incentives with shareholders. There is no evidence of opportunistic selling or material dilution. Accordingly, the disclosure is governance-sound and should not meaningfully influence valuation.

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^*

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)
06/25/2025

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)	06/25/2025		M		58,800(2)	A	(3)	538,651	D
American Depositary Shares(1)	06/26/2025		S		23,669(4)	D	$36.132	514,982	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
Restricted Share Units	(3)	06/25/2025		M			58,800	(5)	(5)	American Depositary Shares(1)	58,800	$0	58,800	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. ADSs acquired upon vesting of Restricted Share Units ("RSUs").

3. Each RSU represents a contingent right to receive one ADS.

4. These ADSs were sold automatically to cover taxes upon vesting of RSUs.

5. The RSUs vest in equal annual installments over four years beginning on 06/25/2023, the first anniversary of the date of grant. Vested shares will be delivered in the form of ADSs to the reporting person following vesting.

	/s/ Bruce Blefeld, Attorney-in-Fact	06/27/2025
	** 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

How many ZLAB shares did CEO Ying Du acquire on 25 June 2025?

She acquired 58,800 ADS through RSU vesting.

Why were 23,669 ZLAB ADS sold on 26 June 2025?

The shares were automatically sold to cover taxes due on the RSU vesting.

What is Ying Du’s total direct ownership after the transactions?

Her direct beneficial ownership is 514,982 ADS.

What do transaction codes “M” and “S” represent in a Form 4 filing?

“M” indicates conversion/exercise of a derivative security; “S” denotes an open-market or private sale.

How many ordinary shares does each ZLAB ADS represent?

Each ADS corresponds to ten ordinary shares of Zai Lab Ltd.