Sam & Ralph, a lingering question about employment

In "Don't Give Up The Sheep", unlike all of the other Sam& Ralph episodes in which he is employed by the same company as Ralph(they punch into the same clock), Sam seems to be independently contracted by a third party, a predator temping agency or is self-employed as a coyote.
It is safe to assume then that between 1942 and 1943, whatever company Ralph worked for bought out Sam, or his employer or hired him on as full time labour.