The patent law in Hong Kong is based on the Hong Kong Patents Ordinance of 27 June 1997, as last amended on 22 February 2008. The Hong Kong patent system is independent from the patent system in the People's Republic of China, in that a "patent granted for Hong Kong SAR takes effect in Hong Kong only and does not provide for protection in the People's Republic of China ". As of November 2019, two types of patents for inventions are available in Hong Kong, the so-called "standard patent" and the "short-term patent":
A standard patent in Hong Kong can be based on a European patent application designating the United Kingdom, or a patent application in the PRC or the UK. When granted, the standard patent is independent from the original foreign patent. However, if a standard patent is based on a European patent, and the European patent is amended or completely revoked following opposition proceedings before the European Patent Office, the proprietor of the standard patent shall notify the Hong Kong Registrar of Patents of the amendment or revocation. In the case of an amendment of the designated European patent, the Registrar shall record the amendment to the specification of the European patent by making an appropriate entry in the Hong Kong patent register and upon that recording the Hong Kong standard patent shall be treated as having been amended in a like manner. In the case of the revocation of the designated European patent, the Registrar shall record the filing, by the proprietor of the standard patent, of details of the revocation and advertise the fact by notice in the official journal. Upon the Registrar advertising details of the revocation of the European patent in the official journal, the Hong Kong standard patent shall be treated as never having had effect.
Short-term patents are also available. Such patents have a maximum term of eight years from the filing date. The short-term patents are subject to a formality examination only, not to a substantive examination on the patentability of the invention.
On 19 December 2019, a new patent system will enter into force in Hong Kong. The new system introduces a so-called original grant patent system for standard patents, allowing standard patent applications to be filed directly in Hong Kong without having to file a patent application outside Hong Kong.