Shares of Square (NYSE:SQ) fell Thursday, declining as much as 16.1%. As of 12:16 p.m. EDT, the stock was down 8.7%.
The decline follows an announcement that the financial-technology company's CFO is stepping down later this year to be CEO at another company.
On Wednesday, CFO Sarah Friar told the company that she plans to take a job as CEO of Nextdoor, a social network for neighbors and communities. To help with the transition, Friar is staying at Square into December, the company said in a press release Wednesday afternoon.
Friar has been integral to Square, serving during a time in which revenue growth has accelerated and the company's stock has skyrocketed. Even after today's decline, shares are up 127% over the past 12 months, and 445% since Square's IPO in November 2015.
Friar has worked at Square for six years.
Square's lead independent director, David Viniar, is heading the search for a new CFO. As a former CFO at Goldman Sachs, Viniar is well qualified to help the company find a quality replacement for Friar.