Fired Employee Sues the Ethereum Foundation and Vitalik Buterin

Kayleen Fulton, who headed the Ethereum Foundation (EF) Protocol Support team and facilitated Ethereum’s All Core Developers calls, says in a federal lawsuit that the EF fired her 13 days after she emailed leadership about her ovarian cancer diagnosis.

The complaint, filed Nov. 4 in U.S. District Court in Colorado, names six defendants: Stiftung Ethereum, the Swiss foundation that operates as the EF; Ethereum Asia Pacific Limited, the Singapore-based EF affiliate on whose behalf she was hired; Lightsource HR Global and Vensure Employer Services, two firms that handled her hiring, payroll and benefits; Bastian Aue, then the EF’s co-executive director; and Vitalik Buterin. Buterin, a Stiftung Ethereum board member sued in his individual capacity, is a defendant in five of the 11 claims, by Unchained’s count.

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The suit centers on the EF’s Mandate, a statement of direction sent to all staff on Feb. 25. That draft carried a “Source Seppuku License” whose author, editors and distributors pledged to “take his or her own life with a sword” if they broke or altered it, the complaint says. When staff were later told to sign a commitment form, one employee asked whether signing bound him to the pledge literally. Aue replied that the pledge was “chosen deliberately, but not meant to be taken literally,” and management “updated the form to specify that the commitment has nothing to do with literal seppuku,” according to the suit.

After a March 2 proposal to remove the clause, 79 employees backed it, the complaint alleges. On March 5, Buterin told staff the document was “continuing to be worked on with significant changes especially to the areas where people have expressed the most concern or confusion,” according to the complaint. The final version, published March 13, kept the pledge text as a small image, the suit says. The copy posted on the EF’s website, checked by Unchained on Nov. 9, has no searchable instance of “seppuku,” though a speech bubble reads, “May the Foundation fall on its own sword if it fails to uphold its solemn promise to Ethereum.”

On March 20, Aue required staff to commit to the Mandate by form and warned in an announcement that “non-submission will be interpreted as a decision to leave,” per the complaint. Fulton, diagnosed on March 19, disclosed the diagnosis in a March 24 email, writing that “at this time” she was “not requesting leave or accommodation.” The next day she sent a letter, ultimately signed by 53 Protocol group members, saying they backed the Mandate’s direction “but cannot in good faith affirm under these conditions,” the complaint says.

Aue fired her by video call on April 6, saying he had lost confidence in her but giving no reason, the suit alleges. Trent Van Epps, the letter’s other organizer, was fired 30 minutes earlier, according to the complaint.

The claims include disability discrimination and retaliation under federal and Colorado law, medical-leave interference and retaliation, and a Colorado aiding-and-abetting claim against Aue and Buterin. Fulton seeks back and front pay plus compensatory and punitive damages, with no dollar figure.

As of Nov. 9, the docket showed no filings after Nov. 4, and the EF, Aue and Buterin had not responded publicly. In a May 14 letter quoted in the complaint, Ethereum Asia Pacific’s counsel denied that Fulton “was subjected to unlawful conduct, economic duress, retaliation,” or “termination in violation of public policy.”

The foundation laid off 54 employees in June, days after Hsiao-Wei Wang stepped down as co-executive director.

Related Listen: Why Ethereum Missionaries Are Leaving the EF: ‘Their Hopes Were Crushed’

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