Two established investors are feeling crypto FOMO. Index and Union Square Ventures have backed the crypto startup Fomo, named after the acronym for “fear of missing out,” the company announced on Monday. Index Ventures led the $75 million Series B fundraise, which valued Fomo at $550 million. Other participants include Zygna cofounder Mark Pincus, Discord CEO Humam Sakhnini, and Eventbrite cofounder Kevin Hartz.

In the doldrums of a crypto down market, it’s rare to see established venture firms that don’t exclusively focus on digital assets lead a fundraise for a crypto startup. Still, Index, which has made its name for bets on non-crypto companies like Figma and Scale AI, isn’t a stranger to the world of blockchain. The Geneva-born firm has backed the stablecoin startup Bridge, which Stripe acquired for $1.1 billion in 2025. Similarly, Union Square Ventures has invested in the blockchain Polygon and crypto developer Matter Labs.

“We’re not doing Fomo because it’s a crypto business,” Julia Andre, a partner at Index Ventures, told me. “We’re doing Fomo because we think there is a market shift there, and they have what it takes to capture this next wave of consumer blockchain trading.”