Short sellers have lost $3.3 billion betting against MicroStrategy this year as bitcoin's record streak has sent shares spiking 180%

• Short sellers have lost $3.3 billion this year betting against Microstrategy's stock, according to data from S3 Partners.
• Bitcoin's record streak has helped MicroStrategy shares spike 180% year-to-date.
• If MicroStrategy keeps rallying, short sellers may be forced to buy more shares to cover their losses, sending them even higher.

Bitcoin's blockbuster rally means it's been a great year so far for MicroStrategy — and a tough one for those betting against the company.

Short sellers have lost around $3.3 billion year-to-date as Microstrategy's stock has soared roughly 180%, according to data compiled by S3 Partners.

Microstrategy — a software company that pivoted in 2020 to amassing one of the world's biggest stashes of bitcoin — has been regularly adding to its pile. The red-hot cryptocurrency has surged more than 1,000% over the period. The company now owns 205,000 tokens worth more than $14 billion, after buying an additional 12,000 bitcoin this week, one of its largest single purchases on record. 

More gains in MicroStrategy stock could squeeze short sellers further, if they're forced to buy back shares in order to cover their losses, something that would push the price even higher.

Optimism around bitcoin is currently being driven by the strong demand and inflows seen from recently approved ETFs, as well as a long-awaited halving event scheduled for April.