Artificial intelligence agents are increasingly stepping beyond the boundaries of individual companies and interacting directly with counterparts at other organizations. Delaware-based startup Causa Prima is building software for that shift, letting AI agents act on companies' behalf and work together to sort out payments between businesses.

On Tuesday, Causa Prima announced a $20 million seed round, closed in September, to expand its agent-to-agent platform, which resolves billing disputes and accelerates payment times between companies and their suppliers. The company was cofounded by German entrepreneurs Maex Ament, Henrik Gebbing, and Philip Stanislaus. It previously raised $10 million in a pre-seed round, bringing total funding to $30 million—all of it assembled within the company's first year.

"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 Partners led the seed round, with participation from QED Investors and FJ Labs, alongside existing investors Creandum, Kfund, and Borusan Ventures. Causa Prima declined to disclose its valuation following the round.

"Every dollar going into [accounts payable and accounts receivable] automation today assumes the bottleneck sits inside one company. Causa Prima is building for the handoff between companies," Base10 general partner Rexhi Dollaku told Fortune in a written statement.

Causa Prima has 25 employees across offices in Madrid and Munich and plans to use the new funding to open a New York office as it expands into the United States.

A large, slow-moving market

Payments between businesses total roughly $98 trillion a year, according to market research firm Fortune Business Insights, while Mastercard puts the broader market opportunity at $125 trillion. Manual approvals can hold up 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.

Causa Prima monetizes that gap by taking a cut whenever its agents successfully negotiate early payments between buyers and suppliers. For suppliers, the logic is simple: cash tied up in unpaid invoices is cash a business cannot spend. How widely companies will trust agents to negotiate on their behalf is the open question Causa Prima's U.S. expansion now faces.

Friends to founders

Ament is no newcomer to the payments industry. Born and raised in Germany, he began his career as a software engineer at SAP, the German multinational whose software helps businesses manage finances and supply chains. He later worked at fintech companies focused on accounts payable and receivable before founding Taulia in 2009, a company specializing in supply-chain finance and electronic invoicing. In 2017, Ament shifted his focus from traditional fintech to blockchain and founded Centrifuge, a decentralized finance company that tokenizes and trades real-world assets.

Causa Prima, in that light, is a return to familiar ground for Ament: both Taulia and the new venture are in the business of getting companies paid faster—only now, software agents handle the negotiating.

Gebbing left the corporate world in 2018 after three years as a senior associate at consulting firm McKinsey & Co. to cofound Finoa, a fintech company that helps bring businesses on-chain.

The two met in Madrid nearly a decade ago while pitching their earlier startups to local venture capitalists. The investors passed on both companies but introduced the founders after noticing that both were German and married to Spanish women.

Years of friendship turned into a business partnership last year, when Gebbing moved into a board role at Finoa to take time off. Instead of relaxing, he and Ament began sketching out ideas around the emerging wave of agentic AI. They brought in Stanislaus, who had previously led engineering under Ament at Centrifuge, as chief technology officer.

While brainstorming, the three realized that internal corporate AI agents were still getting stuck waiting days for humans to answer emails—a bottleneck that prompted them to found Causa Prima early this year. The company's name is drawn from the Latin term for "first cause," a nod to Ament's philosophy that the root cause of all business is simply getting paid.

This story was originally featured on Fortune.com.