NEW YORK — Retail investor darling AMC said Thursday it had successfully completed a large equity sale, raising $587.4 million amid intense volatility in the movie theater stock.

AMC Entertainment said it completed the stock sale of 11.55 million shares, with an average price of $50.85.

Shares of AMC began the year valued at around $2 but have soared amid buying from the so-called “Reddit Revolution” of small investors coordinating on social media in support of beaten-down stocks.

The successful fundraising run boosts AMC’s balance sheet, Chief Executive Adam Aron said in a press release, “providing valuable flexibility to respond to potential challenges and capitalize on attractive opportunities in the future.”

An AMC securities filing earlier Thursday included an unusually blunt investor warning about a trading dynamic that many observers have labeled irrational.

“We believe that the recent volatility and our current market prices reflect market and trading dynamics unrelated to our underlying business, or macro or industry fundamentals, and we do not know how long these dynamics will last,” the company said in a securities filing.

“Under the circumstances, we caution you against investing in our Class A common stock, unless you are prepared to incur the risk of losing all or a substantial portion of your investment.”

Shares were down 3.1 percent at $60.64 in early afternoon trading after getting as low as $37.66 earlier in the session.