He tweeted that Microstrategy is regulated by the SEC, and therefore they would need to disclose Bitcoin sales in SEC filings.
He has talked about the importance and bright future of BTC time and again while defending it from critics.
MicroStrategy is also one of the largest Bitcoin holders, with 129,218 Bitcoins in its treasury.
The address in question, which was the start of the rumor, was also not owned by the company and probably belonged to an exchange.
Plus, they are already in profits as their average buy price is near $30k, which makes it easier for them to stick to an investment from a corporate point of view.