Spicer invented the joint but it required a man called Charles Dana ( company still going strong; http://www.dana.com/)
to exploit the design to the full. This company bought in to EJ Hardy of Birmingham in 1925. Hardy-Spicer produced propeller
shafts with the universal joint under licence. Dana sold their holding in Hardy-Spicer in the 1950s. Hardy-Spicer which was part of
Birfield Ltd still had to pay royalties to Dana. It was in the 1960s that Hardy-Spicer started producing constant velocity
joints on a commercial scale. Birfield was taken over by GKN in the late 1960s.
Here is some bed time reading from which my, hopefully correct, summary is derived:
http://www.competition-commission.org.uk/rep_pub/reports/1960_1969/fulltext/037c01.pdf
http://www.competition-commission.org.uk/rep_pub/reports/1960_1969/fulltext/037c02.pdf
http://www.dana.com/centennial/histbook/
GKN also have a good history bit on their website.
John