As the Trump administration and Silicon Valley work hand-in-hand to integrate more tech into the military, Onebrief, which makes an AI-powered platform that helps military planners build and coordinate complex operational plans, is the latest startup to benefit from the defense tech boom.
The Honolulu-based startup raised a $20 million Series C extension in June, led by Battery Ventures, bringing its total funding to over $120 million and pushing its valuation past $1 billion. That’s an over $400 million increase in valuation since January, when General Catalyst led a $50 million Series C round that valued Onebrief at $650 million.
Onebrief’s software lets the military planners swiftly determine logistical moves and asset allocation for a given situation. These actions are traditionally compiled into extensive planning documents that can span hundreds of pages, Demaree said. Onebrief’s platform handles everything from initial collaboration to issuing orders and mainly uses Claude, Anthropic’s large language model.
“Almost all of the military’s largest plans are built in our software,” cofounder and CEO Grant Demareee added, declining to cite specific plans due to contractual constraints.
He claimed that Onebrief has exhibited roughly 19,600% annualized growth in operational usage, he told Business Insider in an interview.
The fresh cash comes amid surging venture investment in defense tech, now among Silicon Valley’s hottest sectors. VC investments in defense-related companies rose 33% year-over-year to $31 billion in 2024, according to McKinsey. Funding rounds in the first quarter of 2025 totalled $1.4 billion, up from $200 million from the same period last year, according to Pitchbook.
Previously, Demaree served in the 101st Airborne Division, deploying to Liberia and Iraq, and graduated from West Point, where he studied nuclear engineering and international relations.
“I had a couple of deployments that opened my eyes to the reality that military planning is much more important than it gets credit for on the outside — and a much more tractable problem,” Demaree told Business Insider in an interview. “I saw a lot of plans that could take hours or days when they could’ve taken minutes.”
Michael Brown, a partner at Battery Ventures, was motivated by Demaree’s background and the platform’s potential applications to future geopolitical conflicts when leading the firm’s investment in OneBrief.
“The adversarial level of conflict is increasing by the day,” Brown said. “The ability for us as Americans, and our allies, to plan more effectively and quickly will ultimately result in more security for the world.”
Check out the pitch deck that Onebrief used to raise $20 million and become a unicorn.
