As Rolex fans know, JWT became Rolex's advertising agency in 1946; JWT become Pan Am's advertising agency in 1940 and of course the two companies were forever wedded in the 1950s.
JWT Account Supervisor Robert Weikart called the Pan Am account "the truest, bluest, all-woolest, 18-karat, international account at Thompson; Bob Weikart also worked on the Rolex account in the 1960s.
Enclosed are examples of the JWT Pan Am advertisements (three from the 1940s and the last two pictures from 1953).