Patents and Trademarks



1. Patents

Thailand promulgated its first patent law, the Patent Act, in 1979, with significant amendments added in 1992. The Act protects both inventions and product designs and pharmaceuticals. Thailand has numerous bilateral agreements enabling citizens of other countries to file patent applications in Thailand. However, Thailand is not a signatory to the Paris Convention for the Protection of Industrial Property nor a signatory of any other international convention for reciprocal protection of patents.

In December 1997 a new intellectual property and international trade court began operations, which has significantly improved enforcement.  Appeals procedures at the trademark and patent offices have also been streamlined. 


A. Invention Patents 

 For an invention to be patentable, it must 

  • Have novelty

  • Involve an inventive step

  • Be capable of being made or used for some kind of production activity.

Therefore, the following would not qualify for patents:

  • An invention widely known or used by others in Thailand before the filing of the patent application

  • An invention, the subject matter of which was described in a document or printed publication, displayed or otherwise disclosed to the public, in any manner, whether inside or outside Thailand, and whenever the disclosure is by document, printed matter, exhibition or public disclosure by any means whatsoever *

  • An invention that has been granted a patent inside or outside Thailand prior to the date of the patent application

  • An invention that is the subject of an abandoned application in Thailand. This provision does not affect the rights of co-inventors and others who did not apply for such patent shall not be affected

  • An invention for which an application for a patent was filed in a foreign country more than 12 months prior to the date of the patent application, the foreign patent not having been issued.


The revised Patents Act provides that the following are not patentable:

  • Microbes and any components thereof which exist naturally; animal, plant and extracted substances from animals or plants

  • Scientific or mathematical rules or theories

  • Computer programs

  • Methods of diagnoses, treatment and care of human and animal diseases

  • Inventions that are contrary to public order or morality, public health or welfare.


B. Patentable Product Designs 

A product design must be novel in order to be patented: i.e., it must not fall under any of the following conditions:

  • A design widely known or used in Thailand before the filing of the patent application

  • A design picture, the subject matter or details of which have been displayed or disclosed in a document or printed publication inside or outside of Thailand before the filing of the application

  • A design that has been published in the patent journal under Section 65 and 28 before the filing of the patent application

  • A design that so nearly resembles any of the product designs indicated in the points described above that it is apparently an imitation.


C. Product Designs Which Are Not Patentable

  • Product designs which are contrary to public order and good morals

  • Product designs prescribed by Royal Decree.


D. Eligibility

An inventor or product designer has the right to apply for a patent, as does a successor or assignee of the right. An assignment must be made in writing, signed by both the assignor and the assignee.

If, during the course of employment, an employee or contractor creates an invention or product design, the right to apply for a patent belongs to the employer unless otherwise provided by agreement.

The Patent Act requires that an applicant for a patent must be a Thai national or a national of a country which allows persons of Thai nationality to apply for patents in that country.

The patent holder or applicant is entitled to the following rights:

  • A patent for an invention is valid for a period of 20 years from the date of filing the application; a patent for a product design is valid for a period of 10 years from the date of filing the application. The time during which court proceedings regarding the issuance of the patent are in process may be excluded

  • During the period of the validity of the patent, the patent holder has the exclusive right to produce, use, sell, have for sale, offer for sale and import the patented invention or design. Any act performed before the patent is granted, that would otherwise constitute an infringement of the patent, is not deemed an infringement

  • A patent holder has an exclusive right to use the words “Thai Patent”, or  an abbreviation or translation thereof

  • A patent holder may assign the patent to another holder

  • A patent holder may grant a license to another person, subject to restrictions:

    • The patentee shall not impose upon the licensee any condition or restriction or any royalty covenant which is an unfair restraint of competition. Conditions, restrictions or covenants that unfairly restrain competition shall be prescribed by a Ministerial Regulation

    • A patent holder may not require a licensee to pay a royalty or royalties after the validity of the patent has expired

    • Conditions, restrictions, or royalties which are contrary to the above two points are null and void

  • Any assignment or license must be in writing and officially registered.


E. Compulsory Licenses

To discourage monopolies and the acquisition of patents simply to prevent other persons from manufacturing or producing the patented inventions or product designs, Section 46 of the Patent Act provides that:

  • At any time after the expiration of three years from the grant of a patent or four years from the date of filing an application for a patent, any person may apply to the Director-General for a compulsory license if, at the time of the application, it appears that:

    • For no legitimate reason, there is no production of the patented product nor application of the patented process in the country

    • For no legitimate reason, there is no sale of the product produced under the patented process or there are sales of the same at unreasonably high prices or in quantity insufficient to domestic public demand.


F. Cancellation of Patents 

A patent may be canceled under the following conditions:

  • Although a patent has been granted, any person who has an interest in the patent or the public prosecutor may challenge its validity by petitioning the Court for cancellation

  • The Director-General may ask the Board of Patents to cancel a patent in the following cases:

    • If it appears that two years after the issue of a license under Section 50, the licensing has been unable to prevent or alleviate the condition for which a license was issued under Section 46 or 46 bis; or

    • The patentee has licensed another person to exercise the patent rights in violation of Section 41.

Before requesting the Board to cancel a patent, the Director-General shall order an inquiry and notify the patentee and licensees to submit their briefs within 60 days from the date of receipt of notification. The Director-General may summon any person to make statement or deliver any additional documents or items.


G.  Foreign Patents

A foreign patent that has not been granted a separate patent in Thailand receives no protection under the Patent Act. However, foreign patent holders or owners of rights to inventions or designs in foreign countries may enter into business transactions with parties in Thailand and seek equivalent protection through contractual obligations in the form of a licensing agreement.

Since foreign patents, inventions and designs receive no protection under the Patent Act, no civil or criminal action can be taken against a third party who produces products or sells a patented product in Thailand without paying fees to the holder of the foreign patent or who applies in Thailand for a patent on an invention or design already patented in other countries. Nevertheless, legal solutions to such conflicts may be available under separate legislation.


* Disclosure of the essentials or specifications due to or in consequence  of an unlawful act, or disclosure of essentials or specifications by the inventor, including display of the inventor's work at an international exhibition or an official public exhibition provided such disclosure occurred within the period of 12 months prior to the date of filing the patent application shall not be deemed to be disclosure under subsection 2. 



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