Porcelain dating marks
The Public Record office and the British Government tend to enforce these marks and registration numbers.
Companies located outside the UK who have reproduced items, and tried to use a facsimile of the marks or numbering system have been sued, and have had sanctions imposed against them.
The mark can appear in any colour, and on a variety of materials.
The marks almost always included a code to indicate the year of manufacture.
An item with a registry mark or number could have been produced before (less likely as the design would not be protected), or after the date of the registry mark.
The number listed for each year in the table is the first number issued that year. If your number is higher, but less than the number for the next year, then your item had it's design registered during that year.
In April 1988 a system of year of manufacture identification that fitted with that used by Spode was introduced and an M within a diamond was incorporated below the factory mark.
The date included is the year of introduction of the design, not the date of manufacture.
Between 18 specific indications of the year of manufacture are rare but may sometimes be found in the form of the last two figures of the date, eg , printed below the standard mark.
From 1867 a letter system was also used to indicate the year of manufacture. This series of codes continued until the 1960s when the dots are arranged around the R (signifying registered) in a circle.
This tends to protect the use of these marks, and in general restricts them to use on pieces made in the UK.
This protects both collectors and the companies who registered the marks.