Apple doesn't ship bash with iOS, and you don't need signing keys to install modified versions of bash on macOS. But Apple holds lots of patents[1], and while

Apple doesn't ship bash with iOS, and you don't need signing keys to install modified versions of bash on macOS. But Apple holds lots of patents[1], and while it's hard for me to imagine Apple enforcing patents against users of bash, I can easily imagine Apple lawyers making a strong enough case to management that the potential value of all patent licenses that would be implicitly granted by GPL 3 was likely to exceed the cost of feature-freezing or replacing affected macOS components that they would have agreed to a blanket ban. Note that I'm not defending this decision: for the record, I detest software patents, dislike tivoization, and the only problem I have with GPL 3 is when companies that might otherwise contribute to GPL 3 projects are uncomfortable with it. Which is unfortunate, but certainly not a flaw in the license itself. [1] https://patents.google.com/?assignee=%22Apple+Inc%22&oq=assignee:%22Apple+Inc%22 https://patents.google.com/?assignee=%22Apple+Inc%22&oq=assi...