Kayleen Fulton, a former employee of the Ethereum Foundation, has filed a lawsuit against the organization and co-founder Vitalik Buterin, claiming she was fired less than two weeks after revealing a cancer diagnosis. Fulton alleges that her termination on April 6, 2026, was in retaliation for organizing a staff letter opposing a new mandate requiring employees to endorse it to retain their positions. The lawsuit, filed on November 4, 2026, also claims disability discrimination and interference with medical leave rights.