Bitcoin Development Company MicroStrategy (MSTR) added to its mammoth bitcoin (BTC) holdings last week with the purchase of another 21,550 tokens.

The buys were made over the week ended Dec. 8 and the firm paid an average price of $98,783 each, totaling $2.1 billion, according to a Monday regulatory filing . It funded the acquisition by selling roughly $2.13 billion shares during the same period. The company now has an additional $9.19 billion remaining from its previously existing $21 billion at-the-market (ATM) share sales facility.

The latest buying spree brought the firm's BTC holdings to 423,650, or nearly $42 billion worth at current prices. Led by Executive Chairman Michael Saylor, MicroStrategy now holds more than 2% of the 21 million bitcoin that can ever exist.

The purchases took place and perhaps contributed to bitcoin's price action as the crypto crossed above $100,000 last week for the first time in its history with significant U.S. investor activity bidding spot prices higher. Alongside, U.S. spot bitcoin ETFs also saw massive inflows raking in $2.73 billion in fresh funds last week, data compiled by Farside Investors showed.

MicroStrategy shares were down 1% to $395 in premarket trading alongside a modest decline in bitcoin prices to $99,000.

In other corporate adoption news, bitcoin mining firm Riot Platforms (RIOT) announced Monday a $500 million convertible note offering to be used primarily to purchase BTC.