Hi Jane
Whilst it is well recorded that William Ridgway Son and Co registered Catskill Moss pattern on 16 December 1844, the backstamp always seems to be recorded with the initials C C and no mention of Ridgway. As the pattern almost invariably turns up in the US, I assume that C C is for Charles Cartlidge of New York, who were importers for Ridgway in the 1840s and the pattern was exclusive to them. I stress that is an assumption, which I have not tested by proper research. Perhaps somebody can tell us more?
Regards
Andrew