Causa Prima wants AI agents on both sides of the invoice

B2B payments still move at the speed of a human hitting approve. Causa Prima, a Delaware-based startup founded early this year, is betting the fix isn't better software inside one company's finance department — it's agents that negotiate with each other across company lines.

On Tuesday the company announced a $20 million seed round, closed in September, to expand its agent-to-agent platform, which resolves billing disputes and speeds up payment times between companies and their suppliers. Base10 Partners led the round, with participation from QED Investors, FJ Labs, and existing investors Creandum, Kfund, and Borusan Ventures. Causa Prima declined to disclose its valuation following the round.

The raise follows a $10 million pre-seed round, bringing total funding to $30 million. The company has 25 employees across offices in Madrid and Munich and plans to use the money to open a New York office as it expands into the United States. It monetizes by taking a cut whenever its agents successfully negotiate early payments between buyers and suppliers.

Cofounders Maex Ament, Henrik Gebbing, and Philip Stanislaus came to the problem largely through prior fintech work. Ament began his career as a software engineer at SAP SE, later worked at accounts payable and receivable fintechs, founded supply chain finance company Taulia in 2009, and in 2017 founded Centrifuge, a decentralized finance company that tokenizes real-world assets. Gebbing left McKinsey & Company in 2018 after three years as a senior associate to cofound Finoa, which helps bring businesses on-chain. Stanislaus, who had led engineering under Ament at Centrifuge, joined as chief technology officer.

The three sketched out ideas around agentic AI after Gebbing moved into a board role at Finoa to take time off. They found that internal corporate AI agents were still stuck waiting days for humans to answer emails, and named the company after the Latin term for "first cause."

"The status quo today is that a lot of things are still somewhat manual," Ament told Fortune. "What we need is a network of agents, and… the area that felt natural to us was… accounts payable of one company and accounts receivable of another."

Base10 general partner Rexhi Dollaku framed the company's differentiation in terms of where the friction actually lives. "Every dollar going into accounts payable and accounts receivable automation today assumes the bottleneck sits inside one company," Dollaku told Fortune in a written statement. "Causa Prima is building for the handoff between companies."

The market is large and stubbornly slow. Payments between businesses total roughly $98 trillion a year, according to market research firm Fortune Business Insights, while Mastercard estimates the broader market opportunity at $125 trillion. Manual approvals can delay those payments: nearly half of executives working in accounts payable name slow invoice approvals as their biggest challenge, with processing taking more than eight days on average, according to a 2025 report by research firm Ardent Partners.