[theandrewbailey]

IBM might not have the equipment to produce simple low margin parts like keyboards, so it contracts out to a high volume peripheral manufacturer.

[throwaway7767]

The ThinkPad keyboards were indeed made by different manufacturers. When I needed a replacement for my old ThinkPad, there were 3 different FRUs depending on the source manufacturer (ALPS, NMB and Chicony). They each had a different typing feel (one was too mushy for me, another one had about the right amount of tactile feedback and I never got to try the third one).