(Reuters) - Shares of Robinhood Markets ( HOOD ) fell nearly 11% before the market open on Thursday after more than doubling in value this year, as incentives aimed to attract customer assets hurt third-quarter results.

It reduced third-quarter net revenue of the retail trading platform by $27 million, CFO Jason Warnick said late on Wednesday.

Its profit fell short of market expectations, a minor setback for the company that has made significant strides toward becoming a mature, full-fledged financial services provider.

Over the past few months, Robinhood has launched a desktop trading platform, added futures and index options trading and unveiled a credit card as it looks to grow beyond its roots as the go-to platform for social media-savvy investors.

Its shares had surged 120% this year before the quarterly results and were last trading at $25.23 on Thursday.

"We view this quarter as somewhat of a seasonal deceleration in the business after a robust first half... We are not surprised by the significant, negative stock reaction," analysts at J.P. Morgan said.

The brokerage also praised the company's cost discipline as operating expenses dropped 10% in the quarter.

(Reporting by Niket Nishant and Manya Saini in Bengaluru; Editing by Arun Koyyur)