The International Patent Application (PCT - applicarion under the Patent Cooperation Treaty) allows inventors (applicants) to file one general application for a patent (international patent application) at one central patent office, which is called the "receiving office". Such offices may be the Bulgarian Patent Office, the European Patent Office (EPO) or the World Intellectual Property Organization (WIPO). The application is filed in one language and will be valid in each of the 152 PCT Member States that the applicant wishes to designate in the filed international application for patent.

For the applicants for international patents, it should be noted that the criteria of the filed patent applications for these countries are often different. Most national patent offices require that a patent application be filed in the local language. These requirements are the basis for a significant increase in the costs associated with the international patent applications at an early stage in which is assessed the value of the future patenting of the inventions abroad. Such inconvenience is reduced by the choice of filing an international patent application - PCT. The initial incurred costs in filing patent applications at each individual patent office can be significantly reduced or delayed. Therefore, the payment of fees and costs for patent translations and the hiring of patent lawyers connected with the national patent applications are postponed.

 It has to be taken in consideration that the international application for patent (PCT) provides additionally at least 18 months for claiming the priority to the 12- month period, in which the applicants can and have to assess the availability of potential commercialization of their invention in each countriy and then to decide exactly where to seek patent protection for their idea. The PCT application is one of the key aspects of companies' patent strategies and is widely used by applicants to keep their capabilities available for as long as possible. Such a centralized international procedure allows the patent applicant to gain time to decide whether and in which countries he will seek protection of his invention.

Each international patent application (PCT) is further subjected to an international search, and a report is established indicating the state of the art. It is accompanied by a written opinion from an international searching authority on the registerability (patentability) of the said invention, and in particular whether it possesses the obligatory qualities of novelty and inventive step. This procedure is called the "international phase" of the PCT application. The results of the report of an international search allows the applicants to assess their future chances of acquiring national patents, as well as the commercial success of the invention, while their application is still in the international phase, even before paying the due fees for initiating national (regional) phases and, respectively, the subsequent grant of a national patent

Who is entitled to apply for an International Patent Application (PCT)?

In practice, the PCT system can be described as "closed" one. This means that only applicants who are nationals and/or have their registered office in one of the Member States of the PCT may apply for an international patent. These applications (PCTs) may be from several applicants, with the requirement that at least one of them to be a resident of a Member State of the Patent Cooperation Treaty (PCT).

 In each Member State of the PCT, the local law stipulates the criteria for whether the applicant of a PCT application has to be represented by a local patent attorney or an Industrial Property (IP) Representative. In most countries, the authorization of an Industrial Property Representative or patent attorney is not required for applicants residing in the country concerned. Nevertheless, the applicants of the PCT applications are recommended to consult a qualified and experienced patent attorney or IP representative for the preparation of the patent description and filing of the International (PCT) patent application for invention, as well as to professionally protect the interests of the applicants in the relevant Member States of the European Patent Convention ( EPC).

Procedure after the international phase of the PCT application

Following the completion of the international PCT application phase, the applicant needs to select the patent offices in the respective countries or regions in which he/ she wishes patent protection. This action, which must take place within 30-31 months of the priority date of the international patent application, is called "entering PCT application in the national (or regional) phase". This in fact is the phase, in which the patent for the invention is issued. After that, each of the designated national or regional patent offices independently decides on the patentability (registerability) of the international application for patent (PCT) in the respective country.

When the PCT application enters the national phase, instead of the standard patent, in some countries protection of rights in the form of a utility model is also allowed. 

There are also mandatory requirements for the entry of the PCT application into the national phase - the payment of fees specified by the respective national or regional patent offices; providing the translation of the patent description of the application into the corresponding language; an obligation to comply with any additional and/or specific requirements stipulated by the local patent legislation in each of these countries; the appointment of local patent attorneys or IP representatives in each country to defend the applicants' interests before the relevant national patent offices. It is important to clarify that an international PCT application does not lead to the issuance of an international patent, because such a term does not exist in the legislation.

Entry of an international PCT application into a national phase in the Republic of Bulgaria

For the entry of each international PCT application in the national phase in the Republic of Bulgaria, the applicant must have submitted the international application to the Patent Office within 31 months from the initial date of the filing of the application. In case of claimed priority, the period starts from the priority date of the PCT application. It is necessary the due national fees, according to the local legislation to be paid, as well as an accurate translation into Bulgarian language of the description and patent claims to be made.

The Bulgarian patent law allows holders of international PCT applications wishing to enter the national phase in our country to choose what kind of protection they want - such as a Bulgarian patent for invention  or registration of a utility model on the territory of the Republic of Bulgaria, which can be carried out together with the national patent or instead of it.

The foreign applicants who are not based in our country are required to use a qualified local IP Representative or patent attorney to represent them within the national phase of the PCT application before the Bulgarian Patent Office. It is recommended the Bulgarian holders of international PCT applications also to do so - to use the services of a patent attorney with long practice and experience.

Entry of an international patent application in the EURO-PCT phase before the European Patent Office (EPO)

Before  entering the EURO-PCT regional phase, the proprietor must file an international patent application at the European Patent Office (EPO) within the same period of 31 months from the date of filing of the application for patent or from the date of priority of the earliest application. Upon entering the EURO-PCT regional phase, the European Patent Office (EPO) examines the PCT application and makes decision according to criteria for patentability of the  European patent.

The application needs to go through several stages in order to meet a number of mandatory requirements of the European Patent Office (EPO). The minimum requirements to be met include:

– If the EURO-PCT application has not been published in one of the official languages of the European Patent Office (EPO), which are German, English and French, a translation of the patent description into one of the Office's working languages, is required;

– Detailed indication of all documents on which to be based the procedure before the EPO;

 – Payment of due fees when filing a European patent application, fees for designating countries and examination fees, if applicable;  

– Submission of the request and payment of the fee for the examination on the merits                                                 

– Payment of annual patent fees for the third year, if applicable.

Provided that they are nationals or have a permanent seat in the territory of one of the Member States of the European Patent Convention (EPC), the applicants of international PCT applications do not have to be represented by IP professional representatives in the proceedings before the EPO. Although in this case the legislation does not require authorization, the applicants are advised to use the services of an IP representative or a qualified European patent attorney. It is in the interest of the applicants, the international PCT application to be professionally prepared in order to be guaranteed that the desired goal will be achieved and that the procedure before the European Patent Office (EPO) will be carried out as efficiently as possible. All other applicants outside the EPC must be represented by a European patent attorney and the actions in the proceedings before the European Patent Office (EPO) must be carried out through him.

Patent Bureau Plovdiv