• Ordinary Application
• Convention Application
• PCT International Application
• PCT National Phase Application
• Application for Patent of Addition
• Divisional Application

Ordinary Application- An application for patent filed in the Patent Office without claiming any priority of application made in a convention country or without any reference to any other application under process in the office is called an ordinary application. Such an application can be filed by an inventor himself (as an applicant ) or by a person to whom the invention is assigned by the inventor (an assignee is the applicant), without claiming any priority of application made in a convention country or without referring to any other application being processed in the Patent Office. The applicant can be either from India or from abroad.

Convention Application- When an applicant files the application for a patent, claiming a priority date based on the same or substantially similar application filed in one or more of the convention countries, it is called a convention application. In order to get convention status, an applicant should file the application in the Indian Patent Office within twelve months from the date of first filing of a similar application in the convention country. The priority document [Section 138 (1)] and its verified English translation (if required) [Section 138 (2)] also should be submitted by the applicant. A convention application shall be accompanied by a complete specification.

PCT International and National Applications -PCT is an international filing system for patents in which the applicant gets an international filing date in all the designated countries, conferring the late entry (up to 31 months) to the national offices without affecting the priority date. This is a simple and economical procedure for the applicants seeking protection for their inventions in many countries.
Indian Patent Office is a Receiving Office for international applications by nationals or residents of India (see rules 17 to 23). An international application shall be filed with the appropriate office under rule 4 in triplicate either in English or in Hindi language [Rule 19(1)].

An international application [Section 2 (1)(ia)], made according to the Patent Cooperation Treaty [Section 2 (1)(oa)], designating India can enter national phase within 31 months from the priority date of international application or date of filing of international application whichever is earlier. Such an application filed before the Controller in the Indian Patent Office claiming the priority and international filing date is called PCT national phase application. Applicant can enter national phase with a request made in Form 1. The title, description, drawings, abstract and claims filed with the application shall be taken as the complete specification for the purposes of filing in India (Section 10 (4A)). The filing date of the application shall be the international filing date accorded under the Patent Cooperation Treaty [Section 7(1)(B)].

Application of Addition- When an applicant feels that he has come across an invention which is a slight modification of the invention for which he has already applied for/ or has patent, the applicant can go for patent of addition since the invention does not involve a substantial inventive step.

It is also possible to convert an independent patent to a patent of addition at a later date if the subject matter was an improvement in or modification to a main invention for which he holds a patent. There is no need to pay separate renewal fee for the patent of addition during the term of the main patent. A patent of addition expires along with the main patent unless it is made independent according to the provisions in Section 54. However a patent of addition will not be granted unless the date filing of application was the same or later than the date of filing of the complete specification in respect of the main invention. It should be noted that a patent of addition will not be granted before granting of the patent for the main invention.

Provisional Application/Specification- When the applicant finds that his invention has reached a presentable form but not the final shape, he may prepare a disclosure of the invention in the form of a written description and submit it to patent office as a provisional specification which describes the invention.
A provisional specification helps to establish the priority of the applicant over any other person who is likely to file an application for patent in respect of the same invention being developed concurrently. The applicant also gets twelve months time to fully develop the invention and ascertain its market potential without the fear of losing the priority right over the invention. Immediately on receiving the provisional specification the patent office accords a filing date for the application and provides a period up to twelve months for filing the complete specification, during which the applicant can fully develop his invention by himself or with the help of others who are interested in the economic value of the patent. No extension of time is permissible for filing complete specification.

Divisional application (S. 16)- When the application made by an applicant claims more than one invention, the applicant on his own request or to meet the official objection raised by the controller may divide the application and file two or more applications as applicable for each of the inventions. This type of application is divided out of the parent one and is termed as divisional application. The priority date for all the divisional applications will be samse as that claimed by the parent application. It is termed as Ante Dating. The complete specification of the divisional application should not include any matter not in the substance disclosed int eh complete specification of the first application. The reference of the parent application should be made in the body of the specification.