MicroStrategy (MSTR) stock jumped nearly 5% Monday as investors reacted to the company’s latest bitcoin (BTC-USD) purchase and its upcoming addition to the Nasdaq 100.

The software firm-turned-bitcoin whale said in a filing Monday morning that it had acquired an additional 15,350 bitcoins for $1.5 billion. The company now owns roughly 440,000 bitcoins.

MicroStrategy is the largest corporate investor in the cryptocurrency, adopting bitcoin as its primary Treasury reserve asset. The company has been on a bitcoin buying spree since the election of Donald Trump, whose crypto-friendly rhetoric and Cabinet appointments have sent the value of bitcoin soaring as part of the so-called Trump trade.

Some 40% of MicroStrategy's bitcoin position has been acquired in the past 40 days, wrote Bernstein analysts on Monday. Within the past month alone, MicroStrategy purchased more than 100,000 bitcoins for $10.5 billion, SEC filings show.

Bitcoin hit a new record above $106,000 on Monday and has soared more than 50% since Trump’s victory. Trump earlier this month said he would nominate crypto-friendly Paul Atkins to lead the US Securities and Exchange Commission, replacing Gary Gensler, whose reign at the agency saw a massive crackdown on the cryptocurrency. The president-elect said he would create a new White House role for a "crypto czar" to oversee bitcoin policy, appointing former PayPal (PYPL) CEO David Sacks to the position.

Also fueling MicroStrategy’s climb Monday was a recent announcement that the stock will join the Nasdaq 100. MicroStrategy, along with Palantir (PLTR) and Axon Enterprise (AXON), will begin trading as part of the index on Dec. 23, replacing Super Micro Computer (SMCI), Moderna (MRNA), and Illumina (ILMN).

MicroStrategy began investing in bitcoin in 2020 with investments funded by equity, debt financing, and its own cash flows under the leadership of Michael Saylor, who served as CEO until 2022 before assuming the role of chairman.

"We pride ourselves on being at the forefront of institutional bitcoin adoption," CFO Andrew Kang said in the company's Oct. 30 earnings call.

Some doubt the company’s strategy, however. Short seller Citron Research said in November that it had taken a new bet against the stock, saying that shares have "completely detached from BTC fundamentals."

Monday’s gain puts MSTR shares up more than 580% for the year.

Laura Bratton is a reporter for Yahoo Finance. Follow her on X @LauraBratton5.

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