It doesn’t. Uniswap is a decentralized protocol backed by Paradigm (a crypto hedge fund). All fees go to liquidity providers, and none of the founders get a cut from the trades that happen through the protocol.
Currently, the transaction fee paid out to liquidity providers is 0.3% per trade. By default, these are added to the liquidity pool, but liquidity providers can redeem them at any time. The fees are distributed according to each liquidity provider’s share of the pool.
A portion of fees may be dedicated to Uniswap development in the future. The Uniswap team has already deployed an improved version of the protocol called Uniswap v2.