> In many ways, the tuple (BBC Micro, Acorn Computers, arm) is analogous to (IBM PC, Intel, x86).

There was a radical difference in the relationship between the two corporations in each tuple. In the BBC-Acorn relationship, Acorn designed and manufactured the computer; BBC just offered their brand, did marketing, and supplied some high-level requirements. In the IBM-Intel relationship, IBM designed and manufactured the computer, and Intel was the CPU vendor, with many other customers. The 6502s used in the pre-ARM BBC systems were from MOS Technology–or one of their licensees, such as GTE/CMD–so those companies were really the Intel equivalent here