MicroStrategy disclosed a $15 million bitcoin purchase Thursday, as it bought 271 coins at an average price of $55,387 per bitcoin, even as the crypto market raced lower.

The publicly traded business intelligence company has now spent $2.24 billion on bitcoin. It has purchased bitcoin in $15 million tranches at least once a month since March in accordance with CEO Michael Saylor's "sat-stacking" treasury reserve policy. Sat stacking means accumulating bitcoin by buying smaller amounts at certain intervals.

The latest purchase comes as the leading cryptocurrency faces challenges from one of its most vocal corporate backers. Wednesday, Tesla CEO Elon Musk suspended the electric car-maker's bitcoin payments policy because of environmental concerns. Bitcoin plunged to as low as $46,294.72 before recovering to about $50,000, where it now trades, suggesting Saylor's latest purchase preceded Wednesday's news about Tesla.

MicroStrategy's stock price also took a hit in the wake of Musk's announcement. It was down over 7% in pre-market trading Thursday.

MicroStrategy's purchase also comes on the heels of signs of rising inflation as U.S. government data released on Wednesday showed the consumer price index (CPI) rose 4.2% year-over-year in April, the fastest rate in 12 years. Higher inflation will likely lead to higher interest rates, which could mean an end to the cheap money that has helped fuel bitcoin's bull run.