Former Ethereum Foundation Protocol Support lead Kayleen Fulton has filed a federal employment lawsuit against two Foundation-linked entities, Vitalik Buterin and three other defendants, alleging discrimination, retaliation and interference with medical leave rights. According to the 55-page federal complaint filed November 4 in the U.S. District Court for Colorado, Fulton alleges she was dismissed 13 days after telling management she had been diagnosed with ovarian cancer and 12 days after helping organize an employee letter challenging an internal mandate.
The case, No. 1:26-cv-05818, names Ethereum Asia Pacific Limited, Stiftung Ethereum, Lightsource HR Global, Vensure Employer Services, Bastian Aue and Buterin. The allegations have not been adjudicated, and no defendant had filed an answer to the complaint as of November 10. Ethereum Asia Pacific Limited had previously denied unlawful conduct, retaliation and termination in violation of public policy in a May 14 communication described in the filing.
Mandate Dispute Preceded April Termination
The dispute centers partly on the Ethereum Foundation Mandate distributed to staff in February and formally published March 13. Its “Source Seppuku License” includes language stating that an actor should take their own life with a sword for failing to uphold specified open-source commitments. The controversial language remains visible in the Foundation’s published mandate, although management allegedly told staff that it was not intended literally.
Fulton’s complaint says 79 employees voted to remove the section after internal objections. On March 20, Aue allegedly told employees to affirm the Mandate or be treated as leaving the organization. Fulton and Trent Van Epps then organized a March 25 letter signed by 53 members of the Protocol cluster that supported the Mandate’s broader direction while rejecting what they characterized as coerced affirmation. The filing says all 53 signatories kept their positions, while Fulton and Van Epps, the two organizers, were dismissed 30 minutes apart on April 6.
The Mandate’s broader framework centers on censorship resistance, open source, privacy and security, principles Buterin has also emphasized in his recent CROPS-based argument for Ethereum’s long-term value proposition. The lawsuit concerns how that organizational mandate was implemented internally, not any change to Ethereum consensus, protocol governance or network operation.
Fulton Brings 11 Employment Claims
Fulton’s complaint includes claims under the Americans with Disabilities Act and Family and Medical Leave Act, alongside Colorado anti-discrimination and common-law causes of action. She alleges she notified management on March 24 that she was entering an active treatment plan and might require leave or accommodation. Her first four claims include ADA discriminatory discharge and retaliation allegations as well as FMLA interference and retaliation claims.
The filing also challenges a separation agreement Fulton says she signed under duress and later rescinded. The complaint seeks back pay, front pay, liquidated damages, compensatory and punitive damages, statutory penalties and legal costs. Fulton’s base salary had risen to $195,000 after a September 2025 performance review that, according to the complaint, rated her as “Greatly exceeding expectations.” The lawsuit does not specify a total damages figure.
Buterin is also named individually. The complaint cites a recorded conversation several weeks after the dismissal in which Fulton alleges he discussed the organizational incentives created by responding to employee dissent. Those statements are being offered by Fulton as evidence supporting her retaliation theory, rather than representing a judicial finding about Buterin’s role in the termination.
The litigation arrives while the Foundation continues managing substantial operational responsibilities, including protocol research and treasury deployment under its broader institutional strategy, which has included large ETH treasury transactions to fund Foundation operations. For now, however, the Fulton case remains an employment dispute at its earliest procedural stage, with questions around jurisdiction, the contested separation agreement and potential Singapore arbitration likely to arise before any court reaches the merits of her allegations.
