The research and development of a certain technology is endless, and every progress can be patented. For example, Siwutang, which is composed of four kinds of traditional Chinese medicines: Angelica sinensis, Ligusticum Chuanxiong, Radix Paeoniae Alba and Radix Rehmanniae Preparata, is a classic prescription for nourishing blood and is also the most commonly used medicine in gynecology. Even if you can't apply for a patent for the traditional prescription of Siwutang, if you find a new therapeutic use of Siwutang, you can also apply for a patent for this use. If you find a new preparation process that can effectively improve the content of effective components, you can also apply for a patent for preparation process, such as the extraction of effective parts or effective components. Even if you find that one dosage form is obviously superior to other dosage forms, you can apply for a patent for that dosage form. Moreover, after addition and subtraction, these four herbs have evolved into a series of more than 800 "sub-prescriptions" and "sun prescriptions" The famous Taohong Siwu Decoction is made of Siwu Decoction with peach kernel and safflower. It is specially used for treating menorrhagia caused by blood deficiency and blood stasis, as well as threatened abortion and habitual abortion. Siwutang, named Aisiwutang after adding Folium Artemisiae Argyi, Colla Corii Asini and Glycyrrhrizae Radix, is used to treat menorrhagia and is the main prescription for preventing miscarriage, nourishing blood and stopping leakage. After adding Siwu decoction and Sijunzi decoction, it is named "Bazhen decoction", which can not only replenish qi and blood; On the basis of Bazhen Decoction, adding Astragalus membranaceus and Cinnamomum cassia, it has become a perfect nourishing soup that people are very familiar with. Most of the "sons" and "grandchildren" that have been derived and will continue to be derived can apply for patents before disclosure.