The serial number is stamped onto the Ludwig badge fitted to the wooden shell of any drum made after mid-1963. The metal Ludwig badge is either a black or gold keystone shape, a black and chrome triangle or a blue and olive parallelogram.
Ludwig drums made between 1955 and 1963 were not assigned serial numbers. Drums made between 1951 and 1955 were labeled as Leedy & Ludwig and were also not numbered. Manufacturing moved from Chicago to North Carolina in the mid 1980s when Ludwig was bought by the Selmer Company, and some snare drums made during this period may have the badge partially obscured by the hoop.