MicroStrategy shares have gained more than 400% since the start of the year thanks to investor optimism about the software company's strategy of buying bitcoin as the cryptocurrency repeatedly hits record highs.

The company, the largest corporate holder of the cryptocurrency, continued a string of weekly purchases that began in early November.

Regulation of cryptocurrency will relax — sending bitcoin's price up. Investors could profit as MicroStrategy sells stock to buy more appreciating bitcoin.

MicroStrategy stock is trading way above the value of its huge bitcoin stash. That is just the latest example of market valuations that break "the law of one price", writes Heard on the Street's Jonathan Weil.

MicroStrategy announced Monday that it acquired another 15,350 bitcoins, bringing its total holdings to of the token to 439,000.

We’ll just keep buying the top forever; every day is a good day to buy bitcoin,” the founder and chairman of MicroStrategy recently told CNBC. “I would have bought Manhat