Some of the earliest investors in IEX Group recently sold their stakes in the upstart stock exchange, including activist hedge funds Third Point and Pershing Square Capital Management, people familiar with the matter said.

The funds exited their stakes in a transaction that valued privately owned IEX at more than $700m, up from its previous valuation of about $500m, according to people briefed on the deal. Another early investor, Senator Investment Group, and some employees of New York-based IEX also sold shares in the deal, they said. The transaction closed in March but hasn’t been previously reported.