The ARM holding company makes designs and maintains the ARM instruction set and licenses them to manufacturers or designers under a processor license, (for a specific processor without modification), a POP license, (a processor optimized for you if you can't do it yourself), or rarely, an architecture license. Architecture licenses allow you to do whatever you want as long as it implements the ARM ISA. Apple holds an ARM architecture license for the Cortex A15 used to develop the Swift core in the A7 and A8.

See http://www.anandtech.com/show/7112/the-arm-diaries-part-1-ho... for more information.