Account
Cantos is a San Francisco and Los Angeles-based pre-seed and seed venture firm founded in 2016 by Ian Rountree, built around the conviction that the most consequential companies of this century will be built in and around the physical world.
Cantos backs pre-seed and seed stage founders building in defense and national security, advanced manufacturing, energy (including nuclear), aerospace and space infrastructure, critical minerals and materials, robotics, and biotech.
The firm looks for founders working at the frontier of the physical world, companies that cannot pivot their way to greatness and require genuine technical depth, operational intensity, and long time horizons.
Cantos explicitly targets areas where the United States needs to out-build rival systems and out-provide to its populace and democratic allies.
Cantos Fund 4 closed oversubscribed at $70M in early 2026, the firm's second institutional fund and its largest to date.
Fund 1 and Fund 2 were self-funded scout funds; Fund 3 was the first fund raised from outside LPs. LP composition is not publicly disclosed.
Leadership
Ian Rountree is Founder and General Partner, who launched Cantos in 2016 after early operating roles at Invisible Technologies and SoFi. He is based in San Francisco.
Grant Gregory is Partner, joining Cantos in 2024 from Andreessen Horowitz's American Dynamism team where he led investments in Castelion and Salient Motion. He is based in Los Angeles and serves as Board Director at Shinkei and The Lumber Manufactory.
Amee Kapadia is Principal, joining Cantos in 2021 with a focus on AI, biotech, and robotics; she holds an MS in Biomedical Engineering from Johns Hopkins and an MBA from Stanford, co-founded Decoding Bio and the AIxBio Summit, and serves as Board Observer at MoldCo.
Sofia Garcia is CFO, leading finance and operations with prior experience at Slow Ventures, Bracket Capital, and JLL Spark.
Investment Strategy
Cantos writes pre-seed and seed checks, often leading rounds as first institutional check into companies.
The firm is deliberately concentrated, 40+ companies across 10 years reflects a high-conviction, low-volume model. Post-investment support focuses on the specific challenges of hard tech company building: founder recruiting, customer and government relationship development, and navigating the long development cycles that define physical world startups.
The firm also runs Hyperdrive, an operator and advisor network connecting portfolio founders with domain experts across defense, aerospace, manufacturing, and energy.
Notable Investments
United States
