Why do some Coalport marks say “AD 1750” if the factory began in 1795?

Some Coalport hallmarks include "COALPORT" plus "1750 AD," a date earlier than the commonly cited founding year. Reference summaries consider Coalport to have started in 1795 under John Rose, so "1750 AD" functions more as a brand claim than a literal date of the factory's founding. Pieces with this hallmark may still be genuine Coalport; the hallmark alone does not rewrite the company's origins. Collectors treat it like any other hallmark: they interpret it as a clue to a period of production and marketing style, and then compare the shape and decoration to known Coalport ranges.