Crypto industry short sellers have lost at least $6 billion trying to bet against publicly-traded crypto firms this year, due mainly to Bitcoin’s (BTC) outsized rally since Jan. 1.

According to a Dec. 5 report from research firm S3 Partners, traders who bet against publicly traded crypto firms such as Coinbase, MicroStrategy and Marathon Digital are now nursing $6.05 billion in on-paper losses.

The bulk of the losses for short sellers have come in the last three months. After Bitcoin fell to a quarterly low of $25,133 on Sept. 11, short sellers increased their exposure to what they thought was an overbought sector.

Unknown to the traders loading up on shorts, Bitcoin would stage a 77% rally, reaching a new yearly high of $44,481 on Dec. 5, according to Cointelegraph Markets Pro. This rapid upside move induced some $2.65 billion in losses for short sellers.

“Buying-to-cover in the most shorted crypto stocks such as Coinbase Global, MicroStrategy, Marathon Digital Holdings, and Riot Platforms will help push stock prices higher along with the long buying that has driven up stock prices since the end of October,” wrote S3 managing director of predictive analyst Ihor Dusaniwsky in the report.

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Bitcoin’s 161% year-to-date rally has been a significant driver for crypto firm share prices, with Coinbase and MicroStrategy growing 312% and 285%, respectively, within the same time frame.

Bitcoin is trading at $43,964 at the time of writing, with a recent rally attributed to growing anticipation of a potential spot Bitcoin exchange-trade fund approval in January.

Coinbase is the most unsuccessful trade for short sellers, with the firm’s almost 290% rally resulting in more than $3.5 billion in losses for short sellers. Following in a close second, MicroStrategy’s growth has seen short sellers lose more than $1.7 billion.

Despite growing losses, some short sellers have continued to add to their positions, betting that the current rally will soon run out of fuel. Since Bitcoin’s mid-September bounce, $697 million in new short positions have been added.

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