What are the different types of patent applications and procedures?

Patent protection differs from one territorial jurisdiction to another, and here are several different types of patent applications:

US Provisional Patent Application
A Provisional Patent Application is a relatively simple application that does not require claims to be listed. This type of application is available only in the United States. No examination is required for a provisional patent application. Attorney time could be minimal if so desired. Applicants should note, however, that a regular application must be made within 12 months from the date of the provisional filing. The benefit of filing a US Provisional Patent Application is that the application quickly establishes a “priority date” of which the invention is filed, while giving the inventors additional time to decide whether a regular patent application should be filed within the next 12 months. The cost of filing a provisional application is much less expensive than that of filing a regular (non-provisional) application.

Regular patent application (Non-provisional)
A Regular Patent Application requires a full specification and a list of claims. The application will be examined substantially by an examiner of a national patent office. The specification and claims will be published 18 months after the date of filing.

PCT (Patent Cooperation Treaty)
A Patent Cooperation Treaty (PCT) allows an applicant to make a single application, while preserving his or her right to file separate patent applications in some or all of the PCT member states within 30 months from the earliest date of filing. The current PCT member states are listed here.

Reform of the Patent System in Hong Kong
A new patent system has been launched in Hong Kong on 19th December, 2019. It introduces an original grant patent (OGP) system for standard patents, refines the existing short-term patent (STP) system and introduces an interim regulatory measure of prohibiting use of certain confusing or misleading titles and descriptions relating to patent practice in Hong Kong. For further details, please refer to the presentation slides, video (English, Chinese) and the website of Intellectual Property Department (IPD).