content: They aren't buying Github as a product. Both Microsoft and Google could easily build a Github clone in a month. In fact, they probably already have one. What they are buying is YOU, the customer base of Github. Github isn't the product. YOU are the product. The brand of Github is probably worth a few million. But, that brand isn't worth anything without the easily cultivated customer base. The value of the customer base is apparently worth 7 Billion.