Company: ZLAB
Filing Date: 2025-04-29
Form Type: DEFA14A
Source: 0001628280-25-020482
Chunk: 0

Company: Zai Lab Ltd
Filing Date: 2025-04-29
Form: DEFA14A
Chunk 0
---
### UNITED STATES

### SECURITIES AND EXCHANGE COMMISSION

#### Washington, D.C. 20549

#### SCHEDULE 14A

#### Proxy Statement Pursuant to Section 14(a) of the

#### Securities Exchange Act of 1934
<div align='center'>(Amendment No. )</div>

Filed by the Registrant ☒ Filed by a Party other than the Registrant ☐

Check the appropriate box: ☐

| ☐ |     | Preliminary Proxy Statement                                                     |
| ☐ |     | Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2)) |
| ☐ |     | Definitive Proxy Statement                                                      |
| ☒ |     | Definitive Additional Materials                                                 |
| ☐ |     | Soliciting Material under §240. 14a-12                                          |

### ZAI LAB LIMITED
<div align='center'>(Name of Registrant as Specified in its Charter)

(Name of Person(s) Filing Proxy Statement, if other than the Registrant)</div>

Payment of Filing Fee (Check the appropriate box):

| ☒ |     | No fee required.                                                                                   |
| ☐ |     | Fee paid previously with preliminary materials.                                                    |
| ☐ |     | Fee computed on table in exhibit required by Item 25(b) per Exchange Act Rules 14a6(i)(1) and 0-11 |