Page "Chinese herbology" Paragraph 22

These medicines are not patented in the traditional sense of the word.

No one has exclusive rights to the formula.

Instead, " patent " refers to the standardization of the formula.

In China, all Chinese patent medicines of the same name will have the same proportions of ingredients, and manufactured in accordance with the PRC Pharmacopoeia, which is mandated by law.

However, in western countries there may be variations in the proportions of ingredients in patent medicines of the same name, and even different ingredients altogether.