[Form 4] Zai Lab Limited American Insider Trading Activity

Rhea-AI Filing Summary

Zai Lab Ltd (ZLAB) insider activity: Joshua L. Smiley, President and Chief Operating Officer, reported vesting of 15,900 Restricted Share Units (RSUs) on 08/15/2025 that resulted in the acquisition of 15,900 American Depositary Shares (ADSs). A subsequent automatic sale on 08/18/2025 disposed of 6,641 ADSs at a price of $36.236 per ADS to cover taxes. After these transactions the filing reports 76,604 ADSs beneficially owned and 31,800 RSU-related derivative securities reported as beneficially owned. The RSUs vest in equal annual installments over five years beginning 08/15/2023.

Insights

Financial Analyst

TL;DR: Routine executive compensation vesting with partial automatic sale to cover taxes; modest net increase in held ADSs.

The filing documents standard compensation mechanics: 15,900 RSUs vested converting to 15,900 ADSs on 08/15/2025, followed by an automatic sale of 6,641 ADSs at $36.236 on 08/18/2025 to satisfy tax obligations. Reported beneficial ownership after these events is 76,604 ADSs with 31,800 RSU-linked derivative securities outstanding. This is a non-event from an operational perspective but is relevant for share count and insider ownership disclosures.

Corporate Governance Expert

TL;DR: Disclosure aligns with standard Section 16 reporting for executive RSU vesting and tax-withholding sales.

The Form 4 provides clear disclosure of the vesting schedule and the tax-withholding sale mechanism. It also specifies that each ADS represents ten ordinary shares and that RSUs vest annually over five years beginning 08/15/2023. From a governance standpoint the filing documents continued alignment through equity compensation and timely reporting of the related transactions.

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
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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^*

Smiley Joshua L

(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)

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

3. Date of Earliest Transaction (Month/Day/Year)
08/15/2025

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)	08/15/2025		M		15,900(2)	A	(3)	83,245	D
American Depositary Shares(1)	08/18/2025		S		6,641(4)	D	$36.236	76,604	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)	08/15/2025		M			15,900	(5)	(5)	American Depositary Shares(1)	15,900	$0	31,800	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 five years beginning on 08/15/2023, the first anniversary of the date of grant. Vested shares will be delivered in the form of ADSs to the reporting person following vesting.

Remarks:

President and Chief Operating Officer

	/s/ Bruce Blefeld, Attorney-in-Fact	08/19/2025
	** 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 did Joshua L. Smiley report on Form 4 for ZLAB?

He reported vesting of 15,900 RSUs into 15,900 ADSs on 08/15/2025 and an automatic sale of 6,641 ADSs on 08/18/2025 to cover taxes.

How many ADSs does Joshua Smiley beneficially own after these transactions?

The filing reports 76,604 ADSs beneficially owned following the reported transactions.

At what price were the ADSs sold to cover taxes?

6,641 ADSs were sold at $36.236 per ADS on 08/18/2025.

What is the vesting schedule for the RSUs referenced in the filing?

RSUs vest in equal annual installments over five years beginning on 08/15/2023; vested shares are delivered as ADSs.

How many derivative securities (RSU-related) are reported as beneficially owned?

The filing reports 31,800 derivative securities related to RSUs as beneficially owned after the transactions.