 It also had the attraction of appearing before "Apple Computer" in a telephone directory.Around this time, CPU and Andy Hopper set up "Orbis Ltd." to commercialise the Cambridge Ring networking system Hopper had worked on for his PhD, but it was soon decided to bring him into CPU as a director because he could promote CPU's interests at the University of Cambridge Computer Laboratory.CPU purchased Orbis, and Hopper's Orbis shares were exchanged for shares in CPU Ltd. CPU's role gradually changed as its Acorn brand grew, and soon CPU was simply the holding company and Acorn was responsible for development work.