SCHEDULE: RA Capital Management Files Schedule 13G for Zai Lab Limited

RA Capital Management, L.P., Peter Kolchinsky, Rajeev Shah, and RA Capital Healthcare Fund, L.P. have filed a joint Schedule 13G, reporting beneficial ownership of 5.2% of Zai Lab Limited's ordinary shares.

Summary

• RA Capital Management, L.P., Peter Kolchinsky, Rajeev Shah, and RA Capital Healthcare Fund, L.P. (collectively, the "Filers") have entered into a Joint Filing Agreement dated April 6, 2026.
• The agreement allows the Filers to file a single Schedule 13G and/or 13D with the SEC regarding their beneficial ownership of Zai Lab Limited's ordinary shares.
• As of March 30, 2026, the Filers collectively beneficially own 57,435,330 ordinary shares of Zai Lab Limited, representing approximately 5.2% of the class.
• This ownership is based on 1,106,407,390 ordinary shares outstanding as of February 20, 2026.
• RA Capital Healthcare Fund, L.P. directly holds 5,743,533 American Depositary Shares (ADSs), with each ADS representing ten ordinary shares.
• RA Capital Management, L.P. acts as the investment adviser for the Fund and may be deemed a beneficial owner.
• Peter Kolchinsky and Rajeev Shah, as controlling persons of RA Capital Management GP, LLC (the general partner of RA Capital), may also be deemed beneficial owners.
• The Fund has delegated voting and disposal power to RA Capital, and thus disclaims beneficial ownership of the securities it holds for purposes of Section 13(d).
• RA Capital, Dr. Kolchinsky, and Mr. Shah disclaim beneficial ownership of the securities reported, except for the purpose of determining their Section 13(d) obligations.

Sentiment

Score: 5

Explanation: StockSavvy.ai views this as a neutral filing, as it pertains to ownership disclosure rather than company performance or strategic shifts.

Positives

• The filing establishes a clear framework for reporting beneficial ownership of Zai Lab Limited shares by RA Capital entities and individuals.
• The joint filing agreement streamlines reporting requirements for multiple related parties.
• The reporting persons have clearly defined their roles and disclaimed beneficial ownership where applicable, adhering to regulatory guidelines.

Negatives

• The filing does not contain any financial performance data or operational updates for Zai Lab Limited, focusing solely on ownership reporting.
• The disclaimer of beneficial ownership by the Fund, while compliant, may create complexity in understanding ultimate control.

Risks

• Potential for future changes in beneficial ownership that could trigger further SEC filings.
• The concentration of ownership among a few related entities could be perceived as a risk by some investors if not managed transparently.

Future Outlook

The filing itself does not contain forward-looking statements or guidance regarding Zai Lab Limited's future performance. It is a disclosure of beneficial ownership.

Management Comments

• The Reporting Persons expressly disclaim status as a "group" for purposes of this Schedule 13G.
• RA Capital serves as investment adviser for the Fund and may be deemed a beneficial owner, for purposes of Section 13(d) of the Act, of any securities of the Issuer held by the Fund.
• The Fund has delegated to RA Capital the sole power to vote and the sole power to dispose of all securities held in the Fund's portfolio, including the ordinary shares of the Issuer reported herein.
• Because the Fund has divested voting and investment power over the reported securities it holds and may not revoke that delegation on less than 61 days' notice, the Fund disclaims beneficial ownership of the securities it holds for purposes of Section 13(d) of the Act.
• As managers of RA Capital, Dr. Kolchinsky and Mr. Shah may be deemed beneficial owners, for purposes of Section 13(d) of the Act, of any securities of the Issuer beneficially owned by RA Capital.
• RA Capital, Dr. Kolchinsky, and Mr. Shah disclaim beneficial ownership of the securities reported in this Schedule 13G other than for the purpose of determining their obligations under Section 13(d) of the Act, and the filing of this Schedule 13G shall not be deemed an admission that either RA Capital, Dr. Kolchinsky, or Mr. Shah is the beneficial owner of such securities for any other purpose.

Industry Context

StockSavvy.ai notes that this filing is a routine Schedule 13G disclosure, indicating a significant institutional investor's stake in Zai Lab Limited. Such filings are common for investment firms managing substantial portfolios and are crucial for market transparency regarding ownership of publicly traded companies.

Related Party Transactions

• The filing details a Joint Filing Agreement between RA Capital Management, L.P., Peter Kolchinsky, Rajeev Shah, and RA Capital Healthcare Fund, L.P. to jointly file Schedule 13G/13D regarding Zai Lab Limited shares.

Stakeholder Impact

• Shareholders: The filing provides transparency on a significant institutional investor's stake, which can influence market perception and trading activity.
• Management of Zai Lab Limited: Awareness of substantial ownership by RA Capital entities is important for corporate governance and strategic planning.
• Regulators: The filing fulfills SEC disclosure requirements for beneficial ownership.

Next Steps

• The Filers will continue to monitor their beneficial ownership of Zai Lab Limited's ordinary shares and may file amendments to this Schedule 13G as required by SEC regulations.
• The Joint Filing Agreement can be terminated by any Filer with one week's prior written notice or a mutually agreed lesser period.

Key Dates

Keywords

Schedule 13G, Zai Lab Limited, RA Capital Management, Beneficial Ownership, Ordinary Shares, SEC Filing, Joint Filing Agreement, Peter Kolchinsky, Rajeev Shah, RA Capital Healthcare Fund