AMC Entertainment’s shares fell more than 30% on Thursday after an announcement of a stock sale, halting a massive rally led by retailers.

The stock was down 21% to $ 49.38 at 12:13 p.m. ET after falling to $ 37.66 on Thursday. The NYSE temporarily held the stock shortly after it opened due to volatility.

AMC said in a regulatory filing that it may from time to time offer and sell up to a total of 11.55 million shares of its common A shares. Additional shares dilute the value of the existing shares for existing shareholders. Prior to the announcement of the stock sale, stocks were up more than 20% in pre-market trading.

The move comes after AMC rose 95% in Wednesday’s regular trading session to close at an all-time high of $ 62.55. The previous closing record of $ 35.86 was hit in 2015, according to FactSet data.

AMC stock soared as it hit an intraday high of $ 72.62, well above its previous intraday record of $ 36.72.

Trading was interrupted several times on Wednesday as stocks rose more than 100% at times. At the end of the day, more than 710 million shares changed hands. That’s almost double the outstanding shares of AMC. The company’s 30-day average volume is only 143 million shares.

Retail investors – many active on Reddit’s WallStreetBets forum – led the AMC rally, and AMC executives have taken note. On Wednesday, the company announced a new portal to connect with individual investors, offering free popcorn, exclusive demonstrations, and other perks to those who hold its shares.

JPMorgan found that AMC’s retail orders rose to $ 583 million last week, 6.9 standard deviations above last year’s average. According to their quantitative strategy, such an imbalance could lead to further outperformance of the stock in the coming weeks.

AMC stock is up 2850% so far this year, for a market cap of more than $ 31 billion. That makes it worth more than stocks like Delta Air Lines, State Street, and Best Buy.

In a similar event seen in meme stocks like GameStop in January, defiant short sellers increased their stakes on AMC stocks last month, which may have fueled the uptrend. According to S3 Partners, around 18% of the AMC shares available for trading will still be sold short by Wednesday.

On Wednesday, short sellers lost $ 2.8 billion as the stock rose, according to S3. So their losses since the beginning of the year amount to more than 5 billion US dollars, according to S3.

Short sellers such as hedge funds borrow the stock from an investment bank and sell it in the hopes of buying it back at a lower price and returning the stock to make the difference. However, when a stock rises higher, what is known as a short squeeze can occur, forcing investors to buy back the stock in order to reduce their losses.

The fierce trading activity on Wednesday even comes after an investment firm reportedly sold its stake in the company. On Tuesday, AMC announced that it had sold 8.5 million newly issued shares to Mudrick Capital, the latest in a series of capital increases for the stock. The hedge fund later sold all of its AMC shares for a profit on the same day, according to Bloomberg News.

Most Wall Street analysts believe AMC stock will crash at some point. Analysts’ average 12-month target price is $ 5.11, according to FactSet.

– CNBC’s Sarah Whitten, Yun Li and Michael Bloom contributed to this report.

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