Shares of MicroStrategy (MSTR) rose nearly 5% on Monday as investors reacted to the company’s recent Bitcoin (BTC-USD) purchase and its upcoming inclusion in the Nasdaq 100.

The software company-turned-Bitcoin whale said in a filing Monday morning that it had purchased an additional 15,350 bitcoins for $1.5 billion. The company now owns around 440,000 Bitcoins.

MicroStrategy is the largest corporate investor in the cryptocurrency and uses Bitcoin as its primary treasury reserve asset. The company has been on a Bitcoin buying spree since the election of Donald Trump, whose pro-crypto rhetoric and cabinet appointments have driven up the value of Bitcoin in the so-called Trump trade.

About 40% of MicroStrategy’s Bitcoin position was acquired in the last 40 days, Bernstein analysts wrote on Monday. Last month alone, MicroStrategy purchased more than 100,000 bitcoins for $10.5 billion, SEC filings show.

Bitcoin hit a new record of over $106,000 on Monday, rising more than 50% since Trump’s victory. Trump said earlier this month he would nominate crypto-friendly Paul Atkins to head the U.S. Securities and Exchange Commission, replacing Gary Gensler, whose tenure at the agency brought a massive crackdown on cryptocurrency. The president-elect said he will create a new role in the White House for a “crypto czar” to oversee Bitcoin policy, naming former PayPal (PYPL) CEO David Sacks to the position.

MicroStrategy’s rise was also fueled on Monday by the recent announcement that the stock would be added to the Nasdaq 100. MicroStrategy, along with Palantir (PLTR) and Axon Enterprise (AXON), will begin trading as part of the index on December 23, replacing Super Micro Computer (SMCI), Moderna (MRNA) and Illumina (ILMN).

MicroStrategy began investing in Bitcoin in 2020, funded by equity, debt and its own cash flows, under the leadership of Michael Saylor, who served as CEO until 2022 before taking on the role of chairman.

“We are proud to be at the forefront of institutional Bitcoin adoption,” CFO Andrew Kang said in the company’s Oct. 30 earnings release.

However, some doubt the company’s strategy. Short seller Citron Research said in November that it had made a new bet against the stock, saying the stock had become “completely detached from BTC fundamentals.”

Monday’s rise gives MSTR stock a year-to-date gain of more than 580%.

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

Click here for the latest stock market news and in-depth analysis, including stock-moving events

Read the latest financial and business news from Yahoo Finance