Union Pacific purchased the Southern Pacific on Sept. 12, 1996. SP enthusiasts can take pleasure in knowing that technically SP merged UP, not the other way around. On Feb. 1, 1998, the Southern Pacific Transportation Company (a Delaware corporation) merged the Union Pacific Railroad and was then renamed the Union Pacific Railroad Company. Thus ended more than a century of Southern Pacific history.
https://www.trains.com/trn/railroads/history/union-pacific-merger-family-tree/
My grandfather, father, mother, brother and I all worked for the old SP. Varying in length from 1 year to 43 years.