This study identifies and classifies Imperial reign marks on Chinese porcelain from the Ming to the Qing dynasties. Working on the theory that only a few artists created these marks, Christer Loefgren, a former antiquities dealer in Chinese porcelain, created a database with thousands of so-called 'mark and period' brands. This survey, 15 years in the making, covers all the Ming emperors, from the 15th century to the last emperor during the Qing period, including Hongxian, up until 1920.