100+ companies call for increased defenses against AI

In an open letter published Thursday by OpenAI, more than 100 firms called on technology companies, government and organizations of all kinds to increase their cyber defenses. Signed by Anthropic, Google, Microsoft and dozens of other companies, the letter said there is a limited window of time before artificial intelligence-enabled cyberattacks become more widespread and sophisticated.

“The companies and public services our communities depend on — from hospitals to water treatment plants to the infrastructure that powers the internet — are all at risk,” the letter said, enabled by fast-moving AI advancements.

The status quo, the letter said, won’t be enough to defend against attacks. It suggested empowering defenses with cyber-capable AI to speed up security tasks, as well as information and tool sharing so organizations that have successfully protected themselves can share what’s worked.

The companies said a global response is necessary to increase security standards and find solutions to growing threats but said everyone can help reduce risk.

“All organizations, cybersecurity companies, technology partners, government and AI frontier companies have an important role,” they wrote.

The letter urged every organization to make cyber defense an immediate priority for its leadership and for cybersecurity and technology companies to lead the defense response against AI-enabled attacks by continuously testing new cyber capabilities.

Local, national and international governments need to provide funding and coordination so they can share threat intelligence and work together to respond, while leading-edge AI companies should provide responsible access to their models, as well as funding and training, to critical-infrastructure defenders who don’t have enough resources, the letter added.

Earlier this month, at least 12 states, including Michigan, Minnesota and New Jersey, reported their water systems had been hacked, forcing some utilities to switch from automated controls to those that are manually operated. The FBI, Environmental Protection Agency, and Cybersecurity and Infrastructure Security Agency warned in July of cyber threat actors remotely accessing online water and wastewater system infrastructure in several states.

A report from the security company CrowdStrike found that AI-enabled attacks were 89% higher in 2025 than in 2024.

The letter followed billionaire Microsoft co-founder Bill Gates’ warnings about the AI industry in an almost 6,000-word essay published on his own website and in an interview The New York Times on Wednesday. Warning that AI companies were motivated by market incentives without considering society at large, Gates said the AI industry was downplaying its threats to jobs and humanity and said addressing the risks needs to be world’s top priority.

“I don’t like bringing bad news to people, and I don’t like saying that innovation may be a net negative,” Gates told the Times. “But that’s where we are.”

Thursday’s letter also comes as opposition to data centers has grown into a bipartisan issue. While data center companies say their facilities help to generate tax revenues for school districts and reduce property taxes for homeowners, voters are worried about the environmental impacts and the prospect of data centers making their communities more expensive and less livable.

The open letter was signed by entities ranging from banks and software firms to security and mobility companies, including General Motors and Uber.

One of the signatories, Prophet AI, said on its website that it signed the letter because “it reflects what we see in security operations every week, and because its collective cyber defense commitments ask something specific of companies building agentic AI, which includes us.”

In March, the Trump administration released its National Policy Framework for Artificial Intelligence. The industry-friendly proposal called on Congress to stop states from regulating AI development and provides scant oversight of the U.S. AI industry to assert American dominance in the space.

The White House did not respond to a request for a comment in response to the companies’ letter before this story was published.