The UK has a law called "Joint Criminal Enterprise" which is oft critiqued[0]. In America, this same concept is a de-facto legal and social standard to apply "Guilty by Association" wherever it can.
So, in the USA, it can be (incorrectly) argued - by very, very high powered RIAA legal team - that this was aiding and abetting.[1] It's absolutely wrong, but this is the legal world we live in as developers.