The C128 PLA chip is in essence an ASIC. It's using a PLA design but it's only programmable during the mask creation. Using a PLA logic array is just a very eff

The C128 PLA chip is in essence an ASIC. It's using a PLA design but it's only programmable during the mask creation. Using a PLA logic array is just a very efficient way of achieving the design that they wanted. I don't think they sold them to other companies, MOS was at this stage fully part of Commodore. Commodore was really big on vertical integration, they didn't like buying components from other companies if they could help it. They even manufactured a few 74xx logic chips sometimes used in their 8-bit computers.