Why do some Royal Worcester marks mention “Manufacturers to their Majesties”?

This phrase is associated with royal patronage. The Royal Worcester Museum notes that in 1789 King George III granted the city of Worcester the first Royal Warrant to allow the use of the Royal Arms and the words “Manufacturers to Their Majesties”. You may find the related wording on signs, labels or documents relating to certain periods. The wording can help confirm the context of a product’s brand, but the safest way is to do a thorough cross-check, the style of the factory mark, the “Made in England” inscription (if any), and the design features of the object. If the phrase is on a sign that looks modern, or on a product that does not stylistically correspond to the late 18th or late 19th century, consider this a red flag and check it against the museum’s mark references.