Deep tech seed investor Cantos Ventures closes $70M Fund IV

San Francisco-based Cantos Ventures has closed its fourth fund with $70 million in commitments, founder and GP Ian Rountree told Tectonic. The oversubscribed Fund IV follows the firm's $50 million Fund III.

Rountree said the vehicle will back "founders that are ambitious enough to transform the world we live in," across sectors such as aerospace and defense, nuclear, biotech, advanced manufacturing and compute.

Cantos intentionally kept Fund IV relatively small, aiming to maintain high ownership and alignment at the earliest stages. Rountree said this lets the firm "look [founders] in the eye and say [their] company is a meaningful percentage of the net worth of everyone at this firm."

He criticized the tendency of larger funds to drift later-stage, arguing that some "will masquerade as a seed fund, but they’re really treating that early check as a call option to write a bigger check later, once things get interesting, and we just don’t like those incentives."

Cantos has already made ten investments out of Fund IV and expects to cap the portfolio at around 22 companies. The firm plans to lead pre-seed and seed rounds with check sizes ranging from $1.5 million to $4 million.

Founded in 2016, Cantos has focused on deep tech since inception, despite early skepticism from some of Rountree’s mentors, who described the strategy as a "terrible idea" at the time.