René Mayrhofer, Google's director for Android platform security, has resigned after the tech giant signed a contract giving the US Department of Defense access to its artificial intelligence systems for classified military work. According to reports from Business Insider, Mayrhofer confirmed he circulated a farewell letter to colleagues on 18 May, in which he accused Google's top leadership of quietly reversing commitments on both climate and warfare. The director, who joined Google in 2017 and holds a tenured academic position at Johannes Kepler University Linz in Austria, said the company he accepted a job offer from no longer resembles the one he works for today. In his resignation letter titled 'Google Management Has Lost Its Moral Compass,' Mayrhofer wrote that his decision to resign had become 'unavoidable' after Google signed the Pentagon AI deal.
Google announced in late April that it had signed an agreement with the US Department of Defense to provide AI technology for classified operations, including military planning and intelligence gathering. As reported by Business Insider, the deal drew immediate criticism from within the workforce, with some employees having previously lobbied leadership not to proceed. Mayrhofer specifically criticized the contract's open-ended nature, writing that it posed a direct risk to him as a European academic, citing a Politico report in which a Belgian university warned staff against collaborating with US institutions. In his letter, Mayrhofer expressed concern that the deal could include mass surveillance of EU citizens, stating: 'This deal implies that Google (AI) products will likely be used directly against me and mine.'
At the center of Mayrhofer's grievances is what he describes as a pattern of decisions made without internal debate or transparency. According to Business Insider, he pointed to Google's AI principles, first drawn up in 2018, which included explicit pledges not to develop weapons or surveillance tools using AI. In February 2025, Google revised those guidelines and removed those restrictions entirely. Mayrhofer wrote that consequential choices are 'just being decided by top-level management' without proper internal communication. In his letter, he specifically criticized Google's AI principles, stating: 'Google management has quietly abandoned the goals to become carbon-neutral because of the AI model energy usage.'
Mayrhofer was direct about the values driving his decision, describing himself as a longstanding conscientious objector to offensive military engagement. As reported by Business Insider, he wrote: 'I am a pacifist, and have long ago decided that I will not personally work for militaries engaging in offensive warfare (strictly defensive action is somewhat more nuanced).' He also raised concerns about the financial dependence many colleagues face, noting that while he is privileged as a tenured academic, 'many others are not in that situation.' Mayrhofer said he would serve his notice period through August but would 'immediately disconnect from any work on AI systems that might fall under this deal with the DoW.' In his letter, he wrote: 'Proactively harming people is not something that I can or will be involved with.'
Mayrhofer is not the first Google employee to speak out against the military AI contract. According to Business Insider, Andreas Kirsch, a research scientist at Google DeepMind, told the publication in April that he was 'incredibly ashamed' of the company's decision to supply AI for classified work. A Google spokesperson previously told Business Insider the company was 'proud' to be part of a consortium of AI laboratories providing services 'in support of national security,' adding that the company remains committed to the private and public sector consensus that AI should not be used for domestic mass surveillance or autonomous weaponry without appropriate human oversight. Mayrhofer noted in his letter that while there are 'very good people left' on his team, he 'can't/won't personally align with the overall company direction' of working with the US military.
