Roku's post-IPO honeymoon appears to be over.
Shares of the video streaming company fell 12 percent on Tuesday to $20.81 after dropping more than 11 percent on Monday. The stock has lost 30 percent of its value since reaching a high of $29.80 on Friday.
Investors celebrated the IPO last week, lifting Roku shares up 67 percent in their debut after the $252 million offering. Skeptical voices have since emerged.
A Wall Street fund manager sold the stock after the offering, telling CNBC that the initial boost might have been from retail investors rather than institutional money managers. The investor, who asked not to be named to protect future IPO allocations, said he's unclear about "Roku's path to profitability" and its ability to compete with tech giants.
Roku, which is expanding its advertising business, generated $398.6 million in revenue last year, up 25 percent from the prior year. But the company posted a net loss of $42.8 million.
Roku's shares are still well above their IPO price of $14.
"We understand that companies should be profitable but we're still investing today," Steve Louden, Roku's finance chief, said in a statement on Friday. "We have been competing effectively against Apple, Alphabet and Amazon for many years."
— With reporting by CNBC's Tae Kim and Sara Salinas.
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