Hang Seng Indexes Plans Conditional Anthropic Addition to Its Hong Kong-U.S. Tech Index

Hang Seng Indexes Company plans to add Anthropic, PBC (ANT.O), to the U.S.-listed roster of its Hong Kong-U.S. technology index if Anthropic confirms its listing, while revising how the index selects and weights members.

After the listing, it would recalculate the weights of the index’s nine U.S.-listed constituents on an equal-weight basis after the close of the seventh trading day. Anthropic’s addition and the new weights would take effect on the 11th trading day after the listing.

The revised methodology changes the eligible stock universe and selection process. It also updates the rules for fast additions and for replacing constituents that are temporarily removed, and adds a liquidity requirement.

The revised method starts with the index review as of Sept. 30, 2026. Related constituent changes take effect Dec. 14. The index’s name and code will remain unchanged.