Zai Lab (ZLAB) officer auto-sells ADSs to cover RSU tax obligations

Rhea-AI Filing Summary

Zai Lab Ltd officer Joshua L. Smiley reported an automatic tax-related sale of company stock. On April 6, 2026, he sold 3,017 American Depositary Shares (ADSs) at $20.448 per ADS to cover taxes due upon vesting of Restricted Share Units. Each ADS represents ten Ordinary Shares of Zai Lab. After this tax-cover transaction, Smiley directly held 117,602 ADSs, indicating he retained a substantial equity position in the company.

Insider Trade Summary

Net Seller: 3,017 shares ($61,692)

Net Sell 1 txn

Insider Smiley Joshua L

Role See Remarks

Sold 3,017 shs ($62K)

Type	Security	Shares	Price	Value
Sale	American Depositary Shares	3,017	$20.448	$62K

Holdings After Transaction: American Depositary Shares — 117,602 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. These ADSs were sold automatically to cover taxes upon vesting of Restricted Share Units.

Key Figures

Shares sold: 3,017 ADSs Sale price: $20.448 per ADS Holdings after sale: 117,602 ADSs +1 more

4 metrics

Shares sold 3,017 ADSs Open-market sale on April 6, 2026

Sale price $20.448 per ADS Tax-cover sale for RSU vesting

Holdings after sale 117,602 ADSs Direct ownership following transaction

ADS to Ordinary ratio 1 ADS = 10 Ordinary Shares Equity representation relationship

Key Terms

American Depositary Shares, Restricted Share Units, open-market sale

3 terms

American Depositary Shares financial

"Each American Depositary Share ("ADS") represents ten Ordinary Shares of the issuer."

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.

Restricted Share Units financial

"These ADSs were sold automatically to cover taxes upon vesting of Restricted Share Units."

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.

open-market sale financial

"transaction_action": "open-market sale""

An open-market sale is when a shareholder sells existing shares directly on a public exchange to any willing buyer, rather than through a private deal. Think of it like putting goods on a busy market stall where price is set by supply and demand; for investors it matters because such sales increase available supply, can put short-term downward pressure on the stock price, and signal changes in liquidity or investor confidence.

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^*

Smiley Joshua L

(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)

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

2a. Foreign Trading Symbol

3. Date of Earliest Transaction (Month/Day/Year)
04/06/2026

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)	04/06/2026		S		3,017(2)	D	$20.448	117,602	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. 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. These ADSs were sold automatically to cover taxes upon vesting of Restricted Share Units.

Remarks:

President and Chief Operating Officer

	/s/ Bruce Blefeld, Attorney-in-Fact	04/08/2026
	** 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 insider transaction did Zai Lab (ZLAB) report for Joshua L. Smiley?

Zai Lab reported that officer Joshua L. Smiley sold 3,017 American Depositary Shares. The shares were sold on April 6, 2026, in an open-market transaction primarily to cover taxes triggered by the vesting of Restricted Share Units granted as compensation.

At what price did Joshua L. Smiley’s Zai Lab (ZLAB) shares sell on April 6, 2026?

The 3,017 American Depositary Shares sold by Joshua L. Smiley were transacted at $20.448 per ADS. This price reflects the open-market sale used to fund tax obligations that arose when previously granted Restricted Share Units vested into equity.

How many Zai Lab (ZLAB) shares does Joshua L. Smiley hold after this Form 4 sale?

Following the tax-related sale, Joshua L. Smiley directly holds 117,602 American Depositary Shares of Zai Lab. This post-transaction holding shows he continues to maintain a sizable equity stake in the company even after covering tax obligations tied to Restricted Share Unit vesting.

Why were Joshua L. Smiley’s Zai Lab (ZLAB) ADSs sold according to the Form 4?

The Form 4 explains these American Depositary Shares were sold automatically to cover taxes when Restricted Share Units vested. Such transactions are typically administrative, ensuring tax obligations are met without the insider needing to provide separate cash for withholding requirements.

What does each Zai Lab (ZLAB) American Depositary Share represent in Ordinary Shares?

Each Zai Lab American Depositary Share represents ten Ordinary Shares of the issuer. The Form 4 notes that ADSs and Ordinary Shares are fully fungible, and for reporting convenience, the insider’s holdings and transactions are presented in terms of ADSs rather than individual Ordinary Shares.

Was Joshua L. Smiley’s Zai Lab (ZLAB) transaction a routine tax withholding event?

Yes. A footnote clarifies these ADSs were sold automatically to cover taxes upon vesting of Restricted Share Units. That language indicates a routine, compensation-linked tax event rather than a discretionary decision to significantly change his ownership position in Zai Lab shares.