(Reposting my comment here from the other thread) AFAIK, reverse engineering APIs isn’t illegal. [1] There are some (VC backed) start ups that are open about

(Reposting my comment here from the other thread) AFAIK, reverse engineering APIs isn’t illegal. [1] There are some (VC backed) start ups that are open about doing it. Teller API is an example. [2] [1] “Reverse engineering generally doesn't violate trade secret law because it is a fair and independent means of learning information, not a misappropriation. Once the information is discovered in a fair and honest way, it also can be reported without violating trade secret law.“ https://www.eff.org/issues/coders/reverse-engineering-faq https://www.eff.org/issues/coders/reverse-engineering-faq [2] “We reverse engineer these apps to discover their secret API contracts and then implement clients for them.” https://teller.io/ https://teller.io/