Transforming a startup into an industry giant requires founders to be fully aligned regarding fundraising, company structure and the overall mission of the business. Daniela Amodei, co-founder and president of Anthropic, knows this better than most — in 2021, she launched the wildly successful AI company alongside her brother, CEO Dario Amodei, and five other co-founders. And, for entrepreneurs who want to reproduce this type of harmony, Amodei has a trick for finding compatible partners.
“Instead of starting a company together, go on vacation together,” Amodei said recently during a talk at the Stanford Graduate School of Business. “Share a room. Then think, ‘How was that?’
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The AI executive says she was “really lucky” with Anthropic’s group of co-founders. And when it comes to choosing the ideal partner, Amodei looks for strong interpersonal relationships. She has known her brother, Dario Amodei, her whole life, and some of the other co-founders have been part of her circle for 15 years.
Furthermore, most of them had already worked under her or her brother while they all worked at OpenAI. Anthropic’s entrepreneurs thrived within an already established framework of exchanging feedback — and, crucially, according to her, everyone knew “who we were as people.”
The only other essential component is having consensus on what the company is trying to build.
Amodei said Anthropic’s co-founders were united by a desire to achieve something different; the core group had previously worked at OpenAI but split for various reasons, including disagreements over the company’s vision. When launching Anthropic, Claude’s creators were already “on the same page”, according to Amodei.
“If you locked you and your co-founder in another room and asked each of you to write or draw what you were trying to build, you wouldn’t come out with one of you drawing a unicorn and the other a platypus,” the co-founder continued. “This is the kind of situation where you think you’re doing the same thing, but I think it just doesn’t end well.”
How entrepreneurs choose their co-founders
Paul Graham, co-founder of Y Combinator, a Silicon Valley startup accelerator, has already warned entrepreneurs to be careful when choosing a co-founder. Like Amodei, he agrees that good character is extremely important in a partnership — and this is put “severely” to the test when times get tough.
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“People wish they had paid more attention to character and commitment when choosing cofounders, rather than skill. This was particularly true of startups that failed,” Graham wrote in a 2009 essay. “The lesson: Don’t choose cofounders who will jump ship.”
Andy Dunn, co-founder and former CEO of Bonobos, outlined five specific tests that entrepreneurs should do with a potential partner before making “the intense commitment to starting a company together.”
First, the stress test, practicing difficult conversations; then, the test of time, spending a lot of time together to create a bond as “parents” of the business.
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Partners should also play roles, defining who will do what and how decisions change as the company grows; and the “when everything goes wrong” test would serve to prepare a plan for the inevitable departures of partners.
Finally, Dunn recommended analyzing the differences between them to ensure they are not too similar — “very different skill sets” are essential.
“You need to spend enough time together socially, getting to know each other’s friends and family, and treat it like a marriage,” Dunn wrote for Fortune in 2024.
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Venture capital co-founder Jeff Rosenthal and his partner, Patrick Maloney, even gave each other a kind of test before diving into the business for good.
Before creating CIV, an investment platform that invests in and helps expand technology companies, the duo met and tested their dynamics through a written exercise.
Each person detailed their vision for the company in writing — from their office routine to their outlook for the business — exchanging notes “like pen pals” to ensure “nothing got lost in translation.”
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“We wanted to make sure we were aligned in our vision for the kind of company we would build, the kind of culture we wanted, and our expectations of each other,” Rosenthal told Business Insider last year. “And we didn’t want to leave anything unsaid.”
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