PCT National Phase

Overview of PCT National Phase in Thailand

The Patent Cooperation Treaty (PCT) is an international agreement that streamlines the process of seeking patent protection across multiple countries through a single initial application. However, the PCT does not grant international patents—instead, it defers the need to file separate national applications in each country.

PCT National Phase entry refers to the step where applicants move from the international phase to pursue patent protection in individual PCT member states. To obtain a patent in Thailand, applicants must enter the national phase before the Department of Intellectual Property (DIP) within 30 months from the earliest priority date.

Thailand is an increasingly strategic jurisdiction for national phase entry due to its growing economy, regional importance in ASEAN, and manufacturing and R&D activity in sectors such as biotechnology, pharmaceuticals, chemicals, consumer goods, electronics, and automotive.

Who should consider entering the Thai national phase?

Foreign applicants seeking to protect inventions in the Thai market, businesses planning to manufacture or license technology locally, or those facing potential infringement risks in Thailand should seriously evaluate national phase entry. It is particularly relevant for inventors, patent attorneys managing international portfolios, and companies with commercial or supply chain interests in Southeast Asia.

This page explains how to enter the Thailand PCT National Phase, outlining application requirements, timelines, translation rules, and legal procedures to help you secure patent rights for your invention.

Key Requirements for PCT National Phase Entry in Thailand

Time Limit for Entry

Entry must be made within 30 months from the earliest priority date. While late entry is technically possible through a petition for reinstatement, such petitions are granted only in limited circumstances at the discretion of the Thai Patent Office. The applicant must demonstrate that the failure to meet the deadline occurred despite due care being exercised. Because success is rare and the burden of proof is high, timely entry is strongly recommended.

Documents Required at the Time of Filing

These documents must be submitted upon national phase entry:

• Application Form: Signed by a registered Thai patent agent

• PCT Request Form (PCT/RO/101): Along with its Thai translation

• Thai Translation of certain parts of the specification (i.e. title, claims, and abstract)

Documents that May Be Submitted Within 90 Days of Filing Date

Applicants may request an extension of up to 90 days from the filing date to submit the following:

Patent Specification: Must include the title, description, claims, abstract, and drawings (if any).

• Other documents, such as a statement of applicant's rights, assignment deed (if applicable)

Language Requirements

For entering the national phase in Thailand, a Thai translation of the entire international application (as filed) is required. This includes:

• PCT Request Form (RO/101)

• Title, description, claims, abstract, drawings (i.e., the full specification as filed)

Local Representation

Foreign applicants must appoint a registered Thai patent agent or attorney for filing and prosecution.

Filing Process for Thailand PCT National Phase Entry

Step-by-step guide (Entry → Formality Check → Substantive Examination)

Timeline for each stage

Explanation of request for examination and deadlines

Common Mistakes to Avoid

Missing the 30-month deadline

Incomplete or poorly translated documents

Late payment of official fees

Fees and Costs

Government fees (filing, examination, publication, etc.)

Additional costs (translation, agent fees)

Optional: include an estimate range or downloadable fee guide

Tips for a Smooth Entry

Best practices for document preparation

Importance of choosing a skilled local patent agent

Planning for long-term prosecution and maintenance

FAQs

Can I enter after 30 months? Do I need to translate the entire application? Can I amend claims?

PCT Regulations & Filing Resources

Access official texts, procedural rules, and guidance documents essential for understanding and filing under the Patent Cooperation Treaty (PCT).

Treaty

Patent Cooperation Treaty (PCT) (as modified on October 3, 2001)

Regulations

Regulations under the Patent Cooperation Treaty (as in force from July 1, 2024)

Administrative Instructions

Administrative Instructions under the Patent Cooperation Treaty (as in force from July 1, 2024)

Guidance and Materials

Summary of the Patent Cooperation Treaty

The PCT Applicant's Guide

Treaty Preparatory Documents

Contracting Parties (158 members)

Albania, Algeria, Angola, Antigua and Barbuda, Armenia, Australia, Austria, Azerbaijan, Bahrain, Barbados, Belarus, Belgium, Belize, Benin, Bosnia and Herzegovina, Botswana, Brazil, Brunei Darussalam, Bulgaria, Burkina Faso, Cabo Verde, Cambodia, Cameroon, Canada, Central African Republic, Chad, Chile, China, Colombia, Comoros, Congo, Costa Rica, Côte d'Ivoire, Croatia, Cuba, Cyprus, Czech Republic, Democratic People's Republic of Korea, Denmark, Djibouti, Dominica, Dominican Republic, Ecuador, Egypt, El Salvador, Equatorial Guinea, Estonia, Eswatini, Finland, France, Gabon, Gambia, Georgia, Germany, Ghana, Greece, Grenada, Guatemala, Guinea, Guinea-Bissau, Honduras, Hungary, Iceland, India, Indonesia, Iran (Islamic Republic of), Iraq, Ireland, Israel, Italy, Jamaica, Japan, Jordan, Kazakhstan, Kenya, Kuwait, Kyrgyzstan, Lao People's Democratic Republic, Latvia, Lesotho, Liberia, Libya, Liechtenstein, Lithuania, Luxembourg, Madagascar, Malawi, Malaysia, Mali, Malta, Mauritania, Mauritius, Mexico, Monaco, Mongolia, Montenegro, Morocco, Mozambique, Namibia, Netherlands (Kingdom of the), New Zealand, Nicaragua, Niger, Nigeria, North Macedonia, Norway, Oman, Panama, Papua New Guinea, Peru, Philippines, Poland, Portugal, Qatar, Republic of Korea, Republic of Moldova, Romania, Russian Federation, Rwanda, Saint Kitts and Nevis, Saint Lucia, Saint Vincent and the Grenadines, Samoa, San Marino, Sao Tome and Principe, Saudi Arabia, Senegal, Serbia, Seychelles, Sierra Leone, Singapore, Slovakia, Slovenia, South Africa, Spain, Sri Lanka, Sudan, Sweden, Switzerland, Syrian Arab Republic, Tajikistan, Thailand, Togo, Trinidad and Tobago, Tunisia, Türkiye, Turkmenistan, Uganda, Ukraine, United Arab Emirates, United Kingdom, United Republic of Tanzania, United States of America, Uruguay, Uzbekistan, Viet Nam, Zambia, Zimbabwe

International Searching Authorities

PCT Fee Calculator

National Phase Entry Information by Country

Checklist for National Phase Entry in Thailand

Translation requirements and format tips

PCT Time Limit Calculator

Do I need a local agent to file in Thailand?

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