Many of the lesser known back stamps were used by companies whose histories are unknown. While these lesser companies produced fine wares on occasion, it is generally felt that the best examples of Nippon-era hand painted porcelain will carry a back stamp used by the Noritake Company during the Nippon era. The exception to this is Coralene which to the best of our knowledge was never produced by the Noritake Company. [A word of caution: the offshore (mainly China) companies producing "fake Nippon" have perfected the M-in-wreath back stamp. You can no longer tell if it's a fake by looking at the back stamp. See REPRODUCTIONS.
Back stamps are an interesting subject to Club members and you will find discussion of this subject in INCC publications and at our annual CONVENTION.