From Startup Roots to AI Investment: Sarah Guo's Journey to Success

Sarah Guo didn’t just grow up around startups—from her youngest years, she was immersed in one. Her parents ran Casa, a cable and telecom infrastructure startup competing with industry giants like Cisco and Ericsson, serving customers like Time Warner. The team was relatively small and tight-knit, challenging 10,000-person competitors with the strength of their products. Guo was drawn to the startup chaos even then, showing up to the office each day after school, surrounded by snacks and Diet Cokes, tagging along with engineers and learning to code.

“It was really formative for me to see how fun and stressful startups were,” Guo said. “It wasn’t a particularly well-networked group of people, but the product was the best in the market.”

Fast-forward to today: Guo is the founder of Conviction, one of the most talked-about venture firms investing in the hottest area in VC: AI. Since its inception in 2022, Conviction has backed some of the buzziest AI startups, including the legal AI startup Harvey (last valued at $3 billion), the French open-source AI startup Mistral (last valued at $6 billion), the inference platform Baseten (valued at $825 million), and ex-Salesforce co-CEO Bret Taylor’s conversational AI platform Sierra (last valued at $4.5 billion).

Guo is part of a wave of VCs—from legendary firms like Sequoia Capital to accelerators like Y Combinator—looking to invest in this transformational next era of technology. As a sought-after early-stage investor, her firm will be on the ground floor shaping the future of AI.

‘Trust and understanding’

Conviction has so far remained small, with eight people on staff including Guo and former Sequoia partner Mike Vernal.

“I don’t care a lot about scale and power,” says Guo. “I don’t think that’s how entrepreneurs make their decisions about early-stage partners. They care about trust and understanding.”

Before founding Conviction, Guo became a general partner at the esteemed VC firm Greylock while still in her 20s. She left that position behind to strike out on her own, positioning her firm at the center of another trend: the bifurcation of venture.

A challenger?

As firms grow larger, some are leaning into the “collect-them-all” ethos of asset management, departing from venture’s cottage-industry tradition. Guo is sometimes regarded as a challenger to established VC firms, a notion she doesn’t believe fits her philosophy.

“I actually think I’m pretty traditionalist,” says the 35-year-old, who sees venture as a services business.

Life after ChatGPT

The early days of Conviction were a whirlwind; as ChatGPT emerged, Guo was scouting for office space. She had been an early investor in Inflection AI, co-founded by Reid Hoffman and Mustafa Suleyman. What surprised her was the rate of change and how quickly longstanding assumptions became obsolete. In 2016, Guo considered leaving Greylock to start an AI company with Andrew Ng, but decided against it at the time. Now, she acknowledges that the market is ripe for AI ventures.

“I think that’s now true for a lot of things. One of my big beliefs about doing venture in 2025 in AI is that many of your priors don’t make sense anymore.”

Guo hosts a podcast with famed solo GP Elad Gil called No Priors, encapsulating the essence of Conviction’s thesis: we can’t trust previous assumptions, and it takes work to find the truth. Guo publishes all her LP letters, essentially open-sourcing her thinking.

“You are much more likely to find the truth if you are curious and willing to be wrong,” she says.

Guo’s bet that AI matters has proven correct, but she still grapples with the question all investors face: Where is the long-term value in AI?

“The joke was that you have this AI hammer, and that’s not the way you should go looking for companies to invest in. And I’m like, well, it kind of depends: How good is the hammer? AI is a great hammer. So, what are the interesting nails out there in the world?”