How to File an International Patent Application? The PCT System and Priority Right

When protection is sought for an invention in several countries, filing separately in each country can be heavy in terms of time and cost. The PCT (Patent Cooperation Treaty), run within WIPO, is a system that allows protection to be sought in many countries through a single international application.

The PCT system does not by itself grant a patent. In the international phase, an international search report and a written opinion on the invention are prepared. The applicant then enters the national phase in each country where protection is sought, and is examined under that country's own rules.

The priority right is one of the most important parts of this process. Under the Paris Convention, after the first patent filing, the same invention may be filed in other countries within 12 months for patents, and those later filings can keep the date of the first filing. This period is a critical window for planning an international application.

For this reason, the filing strategy should be decided early. The countries in which protection is sought, the size of the market, competition and whether the invention has been published all affect this decision. It is necessary to check from the official sources which countries are party to the PCT and which documents are required at the national phase.

Points to watch:

• The date of the first filing and the priority period must be tracked.
• If the invention has been published or displayed before filing, the novelty assessment may become harder.
• Each country may have different requirements for translation, representation and fees.
• The current time limits and rules of the relevant country must be verified before entering the national phase.

After a first filing in Turkey, when preparing a PCT or other foreign application, keep in mind that the 12-month grace period for the inventor's own disclosure in Turkey (SMK Article 84) may not be applied in the same way elsewhere, and should not be treated as the basis abroad. This exception depends on the source and timing of the disclosure and the conditions of SMK Article 84; disclosure records require case-specific review.

Fees vary by the type of PCT filing and the target countries. The current TÜRKPATENT tariff and the current tariffs of the relevant countries apply; please verify before filing.

When planning internationally, rank countries by more than expected sales. Manufacturing locations, markets for licensing discussions and distribution channels may also matter. Create a decision note for each target: why protection is sought, which technical version is involved and who owns preparation. Translation should preserve technical relationships and consistent terminology. Company details, applicant information and records of the first filing should remain consistent too. Obtaining an application number and obtaining rights in the selected countries are different stages. A planning table should make that distinction visible and show each country’s procedural status separately.

Because an international application process is complex, planning target markets and timing is useful. For our foreign filing service, see: /en/hizmetler/yurt-disi This article is for general information only; for an assessment specific to your file, please consult our patent attorney.