(Updates with the latest stock price movement in the headline and first paragraph.)

MicroStrategy's (MSTR, STRK) shares were down more than 12% in recent Monday trading after the company said it launched an up to $21 billion at-the-market offering for its 8% Series A perpetual strike preferred stock, which is convertible into class A common shares.

Net proceeds will be used for general corporate purposes, including bitcoin purchases and working capital, the company said.

Price: 251.53, Change: -35.65, Percent Change: -12.41