You learn new things everyday. Recently I came across more than one person talking about Utility Model in China. In the recent years, for domestic Chinese who apply for patent, number of applications for Utility Model was more than Invention in the year 2006. However, for foreign applicants, more than 85% of applications were for Invention.
In case you dont know, there are three types of patent in China: Invention, Utility Model and Design.
The one I just learnt in the past week: When filing for Invention Patent, we can also file the Utility Model. Firstly, law will not allow you to own two patent for the same invention, so technically, when the Invention Patent is granted, say, 3 years after application, then you have to withdraw the Utility Model patent. Then why you want to do it?
Say two applications were filed at the same time for the same invention in 1st February 2007. The Utility Model patent will be granted in one year time, say 1st February 2008. With that patent certificate, you can go out protecting your patent right. Three years later (starting from today), the Invention patent is granted in 1st February 2010. You throw away the Utility Model patent certificate, and start using the Invention patent certificate to protect your right. So you buy two years of protection by the Utility Model.
What is the cost? Quite small as compare to other things. Cost of drafting is zero for Utility Model as you file the same copy as the Invention. Filing fee including service charge is small compared to Invention patent.