Chris Krebs, the former head of the US Cybersecurity and Infrastructure Security Agency (CISA) and a longtime Trump target, has resigned from SentinelOne following a recent executive order that targeted him and revoked the security clearances of everybody at the company.

Krebs, a Republican who Trump appointed to lead US cybersecurity operations in 2017, was famously fired via tweet five years ago after he publicly contradicted Trump’s false claims of election fraud. Krebs declared the 2020 US presidential election “the most secure in American history.”

Krebs joined SentinelOne as Chief Intelligence and Public Policy Officer in November 2023 after the security shop snapped up his consultancy, Krebs Stamos Group.

Last week, Trump issued a memorandum revoking security clearances for Krebs and any entities associated with him, including SentinelOne. The order also directed the Attorney General and the Department of Homeland Security to investigate Krebs’ activities during his tenure at CISA, including his assurances of 2020 election security.

“For those who know me, you know I don’t shy away from tough fights,” Krebs said in an email sent to company employees and shared on Wednesday in a LinkedIn post:

According to the executive order, Krebs’ misconduct “involved the censorship of disfavored speech implicating the 2020 election and COVID-19 pandemic.”

“Krebs, through CISA, falsely and baselessly denied that the 2020 election was rigged and stolen, including by inappropriately and categorically dismissing widespread election malfeasance and serious vulnerabilities with voting machines,” the presidential missive. This despite the complete lack of credible evidence of any voting irregularities or inaccurate results in the 2020 election of Joe Biden as president.

SentinelOne had no involvement in Krebs’ past government work, and the move to name the cybersecurity firm appears more retaliatory than regulatory.

In response, the former CISA boss “offered his resignation” to SentinelOne CEO Tomer Weingarten.

“This is my fight, not the company’s,” Krebs says he told his boss.

“So with that, let’s go,” Krebs wrote on LinkedIn and signed off: “Illegitimi non carborundum.” ®