Maxwell Mullen

Maxwell “Max” Mullen is best known as a co-founder of Instacart, which launched in the San Francisco Bay Area in 2012 with Apoorva Mehta and Brandon Leonardo. Instacart’s own company history lists Mullen among the founders, and Y Combinator lists Instacart in its Summer 2012 batch.

Before Instacart, Y Combinator’s profile says Mullen worked at startups including Schematic, an interactive agency acquired by WPP. The same YC profile says he is originally from Los Angeles and graduated from the University of Southern California, where he studied entrepreneurship and cinematic arts.

At Instacart, Mullen’s role evolved from early generalist work into product, employee experience, and culture. In a First Round Review interview, he described doing “everything from running product and design to doing our customer support” in the early days, then later focusing heavily on culture as the company scaled. Instacart priced its IPO on September 18, 2023, and began trading on Nasdaq under `CART` on September 19, 2023.

In 2026, Mullen said he was stepping back from his day-to-day role at Instacart and moving into an advisory role. He said he was “energized to use my experience to help the next generation of founders” as an early-stage investor. His personal site says he has invested in 100+ startups and runs Workshop, a founder community in San Francisco.

• Invests as an individual angel, primarily around pre-seed, seed, and Series A, with public investor databases reporting a $25K-$500K range and $200K sweet spot.
• Focus areas include AI, e-commerce, marketplaces, enterprise applications, and consumer internet.
• Looks for founders with unusually strong conviction. On Uncapped, he said he looks for “irrationally optimistic” founders who can recruit others into their vision.
• For consumer startups, he emphasizes contrarian ideas, taste, speed, conviction, and willingness to look wrong before the market catches up.
• For B2B startups, he says founders need subject-matter depth: they should have lived the problem, know the customers, or have deep insight from working in the space.
• He values early investors who provide capital, help, and signal, and warns founders not to over-optimize only for valuation in early rounds.
• His recent AI comments point to interest in “super agents” and AI-native companies where professionals orchestrate fleets of agents across fields such as software, law, medicine, and accounting.