Antithesis raises $105M series a

◆ Amount

$105M

◆ Announced

3 Dec 2025

◆ Company

◆ Source

◆ The Round

Antithesis raised $105M in series a funding, announced on 3 December 2025, led by Jane Street. The round is tracked live by Fusion42 as part of the Raise fund database and the Scout startup database.

◆ About Antithesis

A deterministic simulation testing platform that helps engineers identify and resolve software bugs more efficiently. Antithesis is based in United States and currently at series a stage, operating in Developer Tools.

◆ Investors

◆ Market context

This funding event is a citable node in Fusion42's market graph: it links Antithesis's Scout profile to the funds behind the round and to related Wire analysis, and is refreshed from public announcements as the round is confirmed or extended. It is the same live market data Arthur reasons over when benchmarking a founder's own raise against what is closing in the market right now.

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