If it isn't already, this will be illegal one day. If this type of finance gimmick catches it would be very dangerous in groups/sectors. It is pure speculation and they are floating convertible notes based on the increased market cap of the stock having just purchased Bitcoin and using the proceeds from the bond sale to buy more. This will wipe out shareholders.
What Michael Saylor is doing here is brilliant - the valuation is far from obscene. Within 10 years, Microstrategy will very likely be the richest company in the world. They already own >2% of all the bitcoin that will ever exist. Difficult to see how anyone can catch up now.<p>Once Microsoft, Google, Apple, USA, China, etc. figure out what's happening (and they will do fast now that MSTR price will be constantly in their face) they aren't going to sit around and watch him buy all the bitcoin.
I'm starting to get the feeling that this MicroStrategy thing is becoming so big that it could have serious fallout. If it gets into the indices especially.
tl;dr; - They're just a shell around a bitcoin leveraged-investment scheme. Like any such scheme, that fabulous when the price of the underlying security (bitcoin) is rising. But disastrous when it's falling.