Hathaway, prepared for a photoshoot, left upon learning of the 24-hour work stoppage.
Around 400 union members protest layoffs and negotiations at Condé Nast
Variety reports workers' strike coincided with the Oscar nominations announcement.
The actor, standing in solidarity, left the shoot before posing for pictures.
Union members from Vanity Fair, Vogue, GQ, and others participate in the protest.
Hathaway's departure was a notable gesture during the ongoing union-corporation talks.
Workers rally outside Condé Nast offices in Manhattan during the strike.
X (formerly Twitter) post thanks Hathaway for not crossing the picket line.
The Guardian seeks comments from Condé Nast and Anne Hathaway regarding the incident.
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