Sean Neville, Circle’s co-CEO, will be stepping down from his role at the end of the month.

Neville, who co-founded the Boston-based payments firm in 2014 with Jeremy Allaire, said in an email obtained by CoinDesk that he notified the company’s Board of Directors during a quarterly meeting. While he will transition out of his role as co-CEO, he will remain on the board as an independent director.

While Neville did not explicitly give a reason for his departure, he said in his email that the company’s recent sale of the Poloniex crypto exchange was one of several factors that made “the time appropriate for me to transition.”

As part of Circle’s board, Neville expects to continue working with CENTRE, the collaboration between Circle and Coinbase which is nominally the issuer of the USDC stablecoin.

“I also expect to propel the mission forward through CENTRE and other new complementary paths that traverse worthwhile challenges in infrastructure, regulatory policy, economics, and product design,” he wrote. “As always, I remain stubbornly optimistic about our ability to devise and execute well-crafted things that improve our collective future.”

However, first Neville intends to take a sabbatical, though he did not provide a timeframe.

Circle was founded as a peer-to-peer payments firm, and became the first company to receive a BitLicense from the New York Department of Financial Services in 2015.