SuperRare, one of the leading marketplaces for non-fungible tokens (NFTs), has cashed in on NFT mania with a $9 million funding round led by tech venture capitalists Velvet Sea and 1confirmation.

Mark Cuban, Chamath Palihapitiya, Marc Benioff (CEO of Salesforce.com) and other well-heeled tech backers also participated in SuperRare’s Series A, the three year-old startup told CoinDesk.

The round comes as crypto worth millions pours into blockchain-linked digital collectibles. While huge sales by relatively established artists such as Beeple catch headlines in mainstream media, an army of lesser-known NFT creators are also selling for six-figures on marketplaces such as SuperRare.

Artists are now generating over $25 million in total sales per month on SuperRare, the startup said. When it launched three years ago, a given month might have seen just $8,000 total. 

But the crowd driving SuperRare’s boon remains surprisingly small. 

Just 727 wallet addresses combined for $5.47 million in SuperRare trading volume in the past week, according to on-chain data site DappRadar. It was the fifth-largest NFT marketplace by volume during that period.

Read also: It’s an NFT Boom. Do You Know Where Your Digital Art Lives?

SuperRare occupies a relatively small but gilded corner of the surging $400 million NFT market. Unlike competitors OpenSea and Nifty Gateway, which are larger and more akin to collectible clearinghouses than swanky digital art showrooms, SuperRare only lists one-for-one editions, making its fare feel almost gallery-like.

Founders John Crain and Jonathan Perkins will invest the capital to fund the platform’s growth, they said. Future features include social rollouts, upgrades to the marketplace backend, a foray into virtual reality and taking steps to ensure featured works remain accessible in the long-term.