Patent Cooperation Treaty (PCT): Everything You Need to Know

The Patent Cooperation Treaty (PCT) is an international agreement administered by the World Intellectual Property Organization (WIPO) that provides a unified procedure for filing patent applications in multiple countries simultaneously. As of 2026, the PCT has 157 contracting states covering virtually every major economy.

The PCT does not grant “international patents” (no such thing exists). Instead, it provides a streamlined process for seeking patent protection in multiple countries through a single initial filing, delaying the expensive national-phase costs by up to 30 months from the priority date.

History and Purpose

The PCT was signed in Washington, D.C. on June 19, 1970, and entered into force on January 24, 1978. It was created to address a fundamental problem: before the PCT, an inventor seeking patent protection in multiple countries had to file separate applications in each country within 12 months of the original filing, each with different format requirements, languages, and fees.

The treaty simplified this by creating a two-phase system:

1. International phase: a single application filed with one receiving office, subjected to one international search
2. National phase: the application enters individual countries for examination under their own patent laws

This system gives applicants up to 30 months from their priority date to decide which specific countries to enter, providing valuable time to assess the commercial potential of an invention before committing to the substantial costs of multinational patent prosecution.

Source: WIPO PCT Overview

How the PCT Filing Process Works

The PCT process follows a structured timeline anchored to the “priority date,” typically the filing date of your first patent application (often a national application or a provisional application).

Month 0: Priority date established Your first patent application (in any PCT contracting state) establishes your priority date. This is the date against which all prior art is measured.

Month 12: File the PCT application You must file your PCT (international) application within 12 months of the priority date. The application is filed with a “receiving office,” either your national patent office or directly with WIPO’s International Bureau in Geneva.

The PCT application must include:

• A request form (PCT/RO/101)
• A description of the invention
• At least one claim
• An abstract
• Any drawings
• The filing fee, search fee, and transmittal fee

Months 16-18: International Search Report (ISR) An International Searching Authority (ISA), such as the USPTO, EPO, or JPO, conducts a comprehensive prior art search and issues a written opinion on patentability. This report is crucial for assessing the strength of your application before committing to national-phase costs.

Month 18: Publication Your PCT application is published by WIPO, making it part of the public record. This publication serves as prior art against later filings by others worldwide.

Months 22-28: Optional International Preliminary Examination You can optionally request a deeper examination (Chapter II) that produces an International Preliminary Report on Patentability (IPRP). This gives you a more detailed assessment of patentability before entering national phase.

Month 30: National phase entry This is the critical deadline. You must enter each country where you want patent protection by filing national-phase applications with translation, paying national fees, and appointing local patent agents. The 30-month deadline from the priority date (or 31 months in some countries) is strict. Missing it typically means losing the right to enter that country.

Source: WIPO PCT Applicant’s Guide

Costs of the PCT Process

The PCT system involves costs at each stage. Here is a realistic breakdown for a US-based applicant in 2026:

International phase costs:

Fee	Amount (USD)
International filing fee	$1,457 (or $291 for electronic filing with fee reduction)
Search fee (USPTO as ISA)	$2,180
Transmittal fee	$240
Attorney preparation	$2,000–$5,000
Total international phase	$5,877–$8,877

Small entities and micro entities qualify for significant fee reductions. Universities and applicants from qualifying countries may pay as little as 10% of the standard international filing fee.

National phase costs (per country):

Country	Typical Cost
United States	$2,000–$4,000
Europe (EPO)	$4,000–$8,000
Japan	$3,000–$6,000
China	$2,000–$5,000
South Korea	$2,000–$4,000
India	$1,000–$3,000

These estimates include official fees, translation costs, and local attorney fees. Entering 5-6 major markets through national phase typically costs $15,000–$35,000 in total.

Source: WIPO Fee Tables

Strategic Benefits of Using the PCT

The PCT offers several strategic advantages beyond simple procedural convenience:

Time to evaluate commercial potential: The 30-month timeline from priority date gives you 18 additional months (beyond the Paris Convention’s 12-month priority period) to assess whether your invention has commercial value before committing to expensive national filings.

Informed decision-making: The International Search Report and Written Opinion provide an expert assessment of your patent’s strength. If the prior art looks unfavorable, you can abandon the application before spending money on national phase entries.

Flexibility in country selection: You can decide which specific countries to enter based on business developments during the international phase. If a new market opens up or a competitor appears in a specific country, you can adjust your filing strategy accordingly.

Simplified amendments: During the international phase, you can amend your claims once as a matter of right (under Article 19), potentially strengthening your application before it enters national examination.

Prior art effect: Even if you ultimately decide not to enter national phase in some countries, your published PCT application serves as prior art worldwide, potentially blocking competitors from patenting similar inventions.

Source: WIPO PCT FAQs

PCT vs. Direct National Filing

Not every situation calls for a PCT filing. Here is when each approach makes sense:

Use the PCT when:

• You plan to seek protection in 3 or more countries
• You need time to secure funding before committing to national costs
• You are uncertain about which markets will be most important
• You want a professional prior art search before investing in prosecution

File directly when:

• You only need protection in 1-2 specific countries
• You have already secured funding and know your target markets
• Speed is critical, as direct filing can be faster in some jurisdictions
• Cost optimization: for 1-2 countries, direct filing is usually cheaper

A common hybrid approach is to file a provisional application in your home country, file a PCT application at month 12, and then enter national phase at month 30 in your chosen countries. This maximizes your optionality at each decision point.

Key Statistics (2025 Data)

• Total PCT applications filed: 278,100 (WIPO Annual Report 2025)
• Top filing country: China (70,015 applications)
• Top corporate filer: Huawei Technologies (6,494 applications)
• Average time to ISR: 15.4 months from priority date
• Most designated countries: United States, EPO, China, Japan, South Korea

Source: WIPO PCT Yearly Review