User:HibiscusKazeneko/Japanese release catalog numbers
Early Japanese catalog numbers are all over the place, with each label having its own format for storing the data. On June 30, 1989, the Recording Industry Association of Japan (RIAJ) issued a whitepaper  ordering its member companies to adopt the XXYZ-12345 format for catalog numbers. XX identifies the record company, Y identifies the medium type onto which the release is pressed and Z is reserved for the use of the record company. The numbers are a general serial number.
In addition to laying down the framework for all catalog numbers, the whitepaper specifies that the two parts be separated with a hyphen. There are two prominent record companies (Sony Music Entertainment Japan and King Records) that do not follow this standard, instead separating the halves of their catalog numbers with a space or not separating them at all.
For a release released before June 30, 1989, enter the catalog number as printed. For a release from after this date (with the exception of Sony-connected releases before April 1, 1991) use a hyphen "-" to separate the two parts. If the numerical part of the catalog number has fewer than 5 digits, do not pad it with zeros. Some labels started with ABCD-1 and worked their way up after the transition, while others only used 4-digit serial numbers (before the whitepaper was amended on December 16, 2005). Always check the release packaging for the true catalog number; shopping sites and record company websites may not always be accurate.
- RIS-502: product record numbering scheme (in Japanese)