A former Ethereum Foundation employee has filed a lawsuit against the organization, Ethereum co-founder Vitalik Buterin, and four other individuals, alleging she was dismissed shortly after disclosing a cancer diagnosis and challenging a new foundation directive. The complaint was filed Nov. 4 in the United States District Court for the District of Colorado by Kayleen Fulton, who is also known in the Ethereum community as “Nixo.”

Fulton claims she led the foundation’s protocol support team and was terminated on April 6—about two weeks after she informed colleagues of her diagnosis. She alleges the dismissal was tied to her involvement in organizing staff objections to the directive, and she seeks compensation for lost pay and unspecified damages.

Key takeaways

Kayleen Fulton (“Nixo”) alleges she was fired 13 days after disclosing her cancer diagnosis and after she helped coordinate a staff letter questioning a foundation directive.
The lawsuit includes claims of disability discrimination, retaliation, and interference with Fulton’s medical leave rights.
Fulton alleges Ethereum co-founder Vitalik Buterin played a role in adopting and enforcing the directive through his position as a board member.
The Ethereum Foundation’s Singapore affiliate, Ethereum Asia Pacific Limited, denied wrongdoing in a May 14 letter referenced in the complaint.

Fulton’s allegations center on diagnosis disclosure and a contested mandate

According to the complaint, Fulton—who headed protocol support—was fired by Bastian Aue, described in the filing as a co-executive director at the time, on April 6. Fulton alleges the termination occurred just 13 days after she disclosed her cancer diagnosis.

Fulton also asserts that she and colleague Trent Van Epps organized a response to the foundation’s mandate. The complaint says the letter was supported by 53 signers and backed the mandate’s stated goals while objecting to an employment-related requirement tied to the directive—specifically, a condition that employees affirm it to keep their jobs.

Fulton claims that two firings followed closely together. She alleges Aue dismissed Fulton and Van Epps about 30 minutes apart on April 6. Alongside the employment actions, the filing argues the foundation’s conduct interfered with her medical leave rights and that the actions amount to retaliation.

Dispute over employment affirmation and language in the mandate

The lawsuit describes controversy not only around how the mandate would be enforced, but also around the wording used in the directive. Fulton’s complaint says some employees objected to a reference to ritual suicide included in the mandate and argues that the context was not understood the same way by staff.

Fulton also alleges that Aue told employees the language was “figurative.” The complaint uses that allegation to underscore the internal disagreement and the significance of the dispute to the employee challenges that preceded Fulton’s dismissal.

Foundation affiliate denies the claims; a separation agreement is cited

In a letter dated May 14 that is quoted in the complaint, a lawyer for the Ethereum Foundation’s Singapore affiliate, Ethereum Asia Pacific Limited, denies that Fulton was subjected to unlawful conduct or retaliation. The letter also states that Fulton’s separation agreement is binding.

Cointelegraph reports that it reached out for comment to the Ethereum Foundation, as well as to Fulton and Van Epps, but had not received responses at the time of publication. The lawsuit itself frames the foundation’s mandate and enforcement efforts as the backdrop for the alleged discriminatory and retaliatory conduct.

The underlying mandate and the foundation’s declared development priorities

The dispute traces back to a directive published by the Ethereum Foundation in March. Cointelegraph previously reported on that mandate, describing the foundation’s intended role in Ethereum’s ongoing and future development. In that earlier coverage, the foundation presented its priorities as including censorship resistance, open-source code, privacy and security, and a focus on protocol upgrades, research, and developer tools.

While the foundation’s mandate was framed publicly around Ethereum ecosystem goals, Fulton’s lawsuit argues that the manner in which the directive was implemented—particularly the requirement that employees affirm it to keep their jobs—became a flashpoint internally. Fulton’s complaint portrays her decision to help organize objections as a trigger for retaliatory actions that culminated in her termination shortly after her diagnosis disclosure.

At this stage, the case turns on allegations contained in the complaint, including Fulton’s claims about timing, decision-making influence by board members, and the relationship between her medical circumstances and her employment outcome. The foundation and the individuals named in the lawsuit have not, based on the record described here, conceded that the firings were improper.

Readers should watch for how the court addresses the discrimination and retaliation claims—particularly any arguments tied to the separation agreement mentioned in the May 14 letter—and whether the case sheds more light on how the March mandate was communicated and enforced across the foundation and its affiliates.