Zai Lab (ZLAB) CEO nets shares after RSU vesting and tax sale

Rhea-AI Filing Summary

Zai Lab Ltd Chairperson and CEO Du Ying reported routine equity compensation activity. On April 1–2, 2026, she exercised vested restricted share units, receiving 20,950 American Depositary Shares (ADSs), each representing ten ordinary shares. Of these, 5,576 ADSs were sold automatically at $20.39 per ADS to cover taxes due at vesting.

After these transactions, Du Ying directly holds 1,125,279 ADSs. Earlier, on March 4, 2026, performance conditions were confirmed for 25,579 performance-based share units, each representing a contingent right to one ADS. These PSUs vest in full on July 2, 2028, subject to continuous service.

Insider Trade Summary

Net Seller: 5,576 shares ($113,695)

Net Sell 8 txns

Insider Du Ying

Role Chairperson & CEO

Sold 5,576 shs ($114K)

Type	Security	Shares	Price	Value
Exercise	Restricted Share Units	6,750	$0.00	--
Exercise	American Depositary Shares	6,750	$0.00	--
Sale	American Depositary Shares	5,576	$20.39	$114K
Exercise	Restricted Share Units	10,800	$0.00	--
Exercise	Restricted Share Units	3,400	$0.00	--
Exercise	American Depositary Shares	10,800	$0.00	--
Exercise	American Depositary Shares	3,400	$0.00	--
Grant/Award	Performance-Based Share Units	25,579	$0.00	--

Holdings After Transaction: Restricted Share Units — 13,500 shares (Direct); American Depositary Shares — 1,130,855 shares (Direct); Performance-Based Share Units — 25,579 shares (Direct)

Footnotes (1)

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. ADSs acquired upon vesting of Restricted Share Units ("RSUs"). Each RSU represents a contingent right to receive one ADS. These ADSs were sold automatically to cover taxes upon vesting of RSUs. Each performance-based share unit ("PSU") represents a contingent right to receive one ADS. The reporting person was granted PSUs on July 2, 2025 based on the satisfaction of specified performance criteria between January 1, 2025 through December 31, 2025. On March 4, 2026, the performance-based vesting conditions were confirmed for PSUs representing 25,579 ADSs. The PSUs vest in full on July 2, 2028, the third anniversary of the date of grant, subject to continuous service. The RSUs vest in equal annual installments over five years beginning on 04/01/2023, the first anniversary of the date of grant, subject to continuous service. Vested shares will be delivered in the form of ADSs to the reporting person following vesting. The RSUs vested in equal annual installments over five years beginning on 04/01/2022, the first anniversary of the date of grant, subject to continuous service. Vested shares will be delivered in the form of ADSs to the reporting person following vesting. The RSUs vest in equal annual installments over four years beginning on 04/03/2025, the first anniversary of the date of grant, subject to continuous service. Vested shares will be delivered in the form of ADSs to the reporting person following vesting.

Key Figures

ADSs acquired via RSU vesting: 20,950 ADSs ADSs sold for taxes: 5,576 ADSs at $20.39 ADS holdings after transactions: 1,125,279 ADSs +3 more

6 metrics

ADSs acquired via RSU vesting 20,950 ADSs RSUs exercised into ADSs on April 1–2, 2026

ADSs sold for taxes 5,576 ADSs at $20.39 Automatic tax-cover sale upon RSU vesting

ADS holdings after transactions 1,125,279 ADSs Direct ownership following April 2, 2026 trades

Performance-based share units 25,579 PSUs Each PSU is a contingent right to one ADS

PSU vesting date July 2, 2028 Full vesting date, subject to continuous service

ADS-to-ordinary-share ratio 1 ADS = 10 ordinary shares Equivalence disclosed for all reported holdings

Key Terms

Restricted Share Units, Performance-Based Share Units, American Depositary Shares, contingent right to receive one ADS, +1 more

5 terms

Restricted Share Units financial

"ADSs acquired upon vesting of Restricted Share Units ("RSUs")."

Restricted share units (RSUs) are a promise from a company to give an employee or service provider actual shares or cash equal to the shares after certain conditions are met, typically staying with the company for a set time or hitting performance targets. Think of them like a time-locked gift card that becomes usable only after you’ve earned it. For investors, RSUs matter because they align employee incentives with company performance and can increase the number of shares outstanding over time, diluting existing ownership and affecting earnings per share.

Performance-Based Share Units financial

"Each performance-based share unit ("PSU") represents a contingent right"

American Depositary Shares financial

"Each American Depositary Share ("ADS") represents ten Ordinary Shares"

American depositary shares (ADSs) are a way for investors in the United States to buy shares of foreign companies without dealing with international markets directly. They represent ownership in a foreign company's stock and are traded on U.S. stock exchanges, making it easier for American investors to buy, sell, and own parts of companies from around the world.

contingent right to receive one ADS financial

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

continuous service financial

"The PSUs vest in full on July 2, 2028 ... subject to continuous service."

Form 4 Insider Transactions: What Each Field Means →

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 MASSACHUSETTS 02142

(City) (State) (Zip)

UNITED STATES

(Country)

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

2a. Foreign Trading Symbol

3. Date of Earliest Transaction (Month/Day/Year)
03/04/2026

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
American Depositary Shares(1)	04/01/2026		M		10,800(2)	A	(3)	1,120,705	D
American Depositary Shares(1)	04/01/2026		M		3,400(2)	A	(3)	1,124,105	D
American Depositary Shares(1)	04/02/2026		M		6,750(2)	A	(3)	1,130,855	D
American Depositary Shares(1)	04/02/2026		S		5,576(4)	D	$20.39	1,125,279	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
Performance-Based Share Units	(5)	03/04/2026		A		25,579		(6)	(6)	American Depositary Shares(1)	25,579	$0	25,579	D
Restricted Share Units	(3)	04/01/2026		M			10,800	(7)	(7)	American Depositary Shares(1)	10,800	$0	10,800	D
Restricted Share Units	(3)	04/01/2026		M			3,400	(8)	(8)	American Depositary Shares(1)	3,400	$0	0	D
Restricted Share Units	(3)	04/02/2026		M			6,750	(9)	(9)	American Depositary Shares(1)	6,750	$0	13,500	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. Each performance-based share unit ("PSU") represents a contingent right to receive one ADS.

6. The reporting person was granted PSUs on July 2, 2025 based on the satisfaction of specified performance criteria between January 1, 2025 through December 31, 2025. On March 4, 2026, the performance-based vesting conditions were confirmed for PSUs representing 25,579 ADSs. The PSUs vest in full on July 2, 2028, the third anniversary of the date of grant, subject to continuous service.

7. The RSUs vest in equal annual installments over five years beginning on 04/01/2023, the first anniversary of the date of grant, subject to continuous service. Vested shares will be delivered in the form of ADSs to the reporting person following vesting.

8. The RSUs vested in equal annual installments over five years beginning on 04/01/2022, the first anniversary of the date of grant, subject to continuous service. Vested shares will be delivered in the form of ADSs to the reporting person following vesting.

9. The RSUs vest in equal annual installments over four years beginning on 04/03/2025, the first anniversary of the date of grant, subject to continuous service. Vested shares will be delivered in the form of ADSs to the reporting person following vesting.

	/s/ Bruce Blefeld, Attorney-in-Fact	04/03/2026
	** 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)

FAQ

What did Zai Lab (ZLAB) CEO Du Ying report in this Form 4?

Du Ying reported routine equity compensation activity, including RSU vesting into 20,950 ADSs and an automatic sale of 5,576 ADSs to pay taxes. She also reported performance-based share units tied to future vesting, all held directly in her name.

How many Zai Lab (ZLAB) ADSs does Du Ying hold after these transactions?

After the reported transactions, Du Ying directly holds 1,125,279 American Depositary Shares. These holdings reflect RSUs that vested into ADSs minus ADSs automatically sold to cover tax obligations, according to the Form 4 disclosure and accompanying explanatory footnotes.

Were Du Ying’s Zai Lab (ZLAB) share sales discretionary or for taxes?

The 5,576 ADSs were sold automatically to cover taxes upon RSU vesting, according to a footnote. This indicates the disposition was for tax withholding rather than a discretionary open-market sale motivated by a change in the CEO’s investment view.

What performance-based share units did Du Ying receive from Zai Lab (ZLAB)?

Du Ying was granted 25,579 performance-based share units, each representing a contingent right to one ADS. Performance criteria for these units were confirmed on March 4, 2026, and the PSUs vest in full on July 2, 2028, subject to continuous service.

How are Zai Lab (ZLAB) American Depositary Shares related to ordinary shares?

Each American Depositary Share represents ten ordinary shares of Zai Lab, and the two are fully fungible. The Form 4 states all amounts are reported in ADS terms, helping investors directly compare derivative awards and resulting share holdings.

What RSU vesting schedule applies to Du Ying’s Zai Lab (ZLAB) awards?

Footnotes explain various RSU grants vest in equal annual installments over four or five years, starting one year after grant. Upon vesting, the RSUs deliver ADSs to Du Ying, with some shares automatically sold to satisfy tax obligations at the time of vesting.