OpenAI said it will provide the European Union with access to GPT-5.5-Cyber, a cybersecurity-focused version of its latest AI model, as Brussels expands oversight of advanced AI systems and cyber capabilities. The announcement marks a significant step in the EU’s effort to directly evaluate frontier AI models before wider deployment.
According to OpenAI, European businesses, governments, cybersecurity authorities, and institutions including the EU AI Office will receive access to the model as part of a limited preview program for vetted cybersecurity teams. The company said the initiative falls under a broader “OpenAI EU Cyber Action Plan” focused on improving defensive cyber capabilities across Europe.
The move comes roughly one month after Anthropic introduced Mythos, its advanced cybersecurity-focused model that sparked concerns among governments and enterprises because of its ability to identify software vulnerabilities at large scale. Unlike OpenAI, Anthropic has not yet granted EU institutions preview access to the model.
European Commission spokesperson Thomas Regnier confirmed that OpenAI has already exchanged information with the Commission and that additional meetings are scheduled this week to discuss access and oversight arrangements.
“We welcome OpenAI’s transparency and intent to give commission access to new model,” Regnier said during a press briefing. He added that the arrangement would allow European authorities “to follow deployment of the model very closely, and address security concerns.”
Regnier said the Commission has also held “four or five” meetings with Anthropic regarding Mythos, but discussions remain at an earlier stage.
“The discussions with Anthropic are not yet at the same stage as the solution we have on the table from OpenAI,” he said.
OpenAI framed the agreement as part of a broader push toward collaborative oversight of cyber-capable AI systems.
“AI labs like ours shouldn’t be the sole arbiters of cyber safety as resilience depends on trusted partners working together,” said George Osborne, OpenAI’s head of OpenAI for Countries.
He added that advanced cyber models “should be available for Europe’s many defenders, not just the few.”
Europe Pushes For Direct Access To Frontier AI Systems
The agreement reflects how European regulators are moving beyond traditional compliance discussions and toward direct technical engagement with frontier AI models. Rather than relying only on company disclosures, EU institutions are increasingly seeking hands-on access to evaluate deployment risks, security implications, and potential misuse scenarios.
Cybersecurity models have become a particular focus because of their dual-use nature. Systems capable of identifying vulnerabilities can help defenders secure critical infrastructure, but they can also accelerate offensive cyber operations if misused.
OpenAI’s decision to provide access gives the company a more cooperative position with European regulators at a time when AI oversight under the EU AI Act is becoming more aggressive and technically detailed.
Anthropic Faces Growing Pressure Over Mythos Access
Anthropic’s reluctance to provide similar access to Mythos could increase regulatory pressure as governments demand greater visibility into frontier AI systems with national security implications.
Mythos has already attracted attention because of reports that it uncovered tens of thousands of software vulnerabilities, including flaws in widely used infrastructure and legacy systems. Anthropic has restricted access to the model because of concerns that the findings could be exploited by malicious actors.
The divergence between OpenAI and Anthropic also highlights an emerging split in how leading AI labs approach government oversight. Some companies are moving toward structured collaboration with regulators and security agencies, while others remain more cautious about sharing highly capable cyber models before safeguards and patching processes are in place.
