Routledge and Kegan Paul Ltd. was formed in 1912 as an amalgamation of the firms of Routledge & Sons (incorporating J C Nimmo Ltd) and Kegan Paul, Trench, Trubner & Co (incorporating Henry S. King). (from https://www.ucl.ac.uk/library/special-collections/a-z/routledge)
NB. currently unclear when the name Routledge & Kegan Paul (minus the "Limited") came in to use. The limited company was formed in 1912 (or 1902) but Routledge & Kegan Paul may not have been in use until 1947. Further info needed.