There is no such thing as a 'worldwide’ patent given that patent protection is territorial in nature. In this connection, each country or jurisdiction will independently assess and decide whether it will grant a patent in accordance with its own national patent laws.

In other words, a patent granted in Hong Kong does not have any legal effect in the Mainland China, nor elsewhere in the world. Similarly, a patent granted in the Mainland China, or elsewhere in the world, does not have any legal effect in Hong Kong.

You therefore need to consider applying for a patent in each of those countries where you anticipate manufacturing, selling, exporting or otherwise commercially exploiting (such as by licensing) your patented product or process.

There are two basic ways of applying for a patent in multiple countries:

1. You may file a separate national application in each country where you elect to seek patent protection (by national route).

   You might do this where you decide to apply for patents in a small number of countries only.

   In particular, you will have to do this in relation to patents that you seek in countries that are not members to the Patent Cooperation Treaty (PCT) (e.g. some South American, African, and Middle Eastern countries) – see point 2 below.

2. You may file an application under the PCT (by international route).

   While the filing of a PCT application is sometimes perceived as a means of acquiring a "worldwide" patent grant, it should be noted that such filing is essentially a means of streamlining the patent application process when you want to apply for national patents in multiple countries being the PCT contracting states.

   The filing of a PCT application enables you to apply for patent grants in PCT member countries at the same time with far less expense thereby dispensing with the need for making a separate national application in each individual country.

   You however need to decide at a later stage of your PCT application which PCT member countries you wish to pursue your patent application in by requesting your PCT application to enter into the national phase. If you make a PCT application designating China, you can elect to seek standard patent (R) or short-term patent protection in Hong Kong after the PCT application has entered its national phase in China.