The Patent Co-operation Treaty PCT

The procedure under the Patent Co-operation Treaty (PCT) provides for centralised filing and prosecution of patent applications in a single language before a single authority.

International applications progress through two main phases, the “International Phase” before the PCT authorities where prosecution is in a single language, followed by the “National Phase” where prosecution continues before one or many selected individual national or regional patent offices.

In the international phase, PCT procedure is divided into two sub procedures, Chapter I procedure in which centralised filing for a number of states and where a centralised search is provided, with a lower level of examination, and Chapter II examination in which centralised examination before a single authority in a single language is provided to a higher level. Chapter II examination is optional, but recommended.

At the end of the international PCT procedure, which lasts in general a maximum of 30 months from the first filing date (or the priority date), to continue protection before any national or regional patent office, separate individual patent applications must be filed at those particular national or regional offices. This stage is known as the national/regional phase of the international application. Once the patents enter their national and regional phases, further search and examination occurs in those countries. At this stage, proceedings are in the languages of the selected national states.  As of October 2005, 128 countries are party to the Patent Co-operation Treaty (see attached appendix).

Whilst the cost of filing and prosecuting an international application under the PCT is in addition to the costs of prosecuting the national patent applications in the national/regional phases, there is still a significant cost saving available compared to the alternative of multiple foreign national patents. Firstly, the cost of filing in a number of different countries is delayed for up to 30 months compared to filing applications directly at those national/regional offices. Secondly, much of the search and prosecution procedure can be carried out in a single language before a single authority, avoiding much of the translation and administrative work which would otherwise occur individually before the respective national or regional patent offices.

The international authorities are incapable of actually granting a patent at the end of the international phase, this only occurs during the subsequent national phase. However, they do produce an international preliminary examination report giving their comments on the novelty, inventive step and industrial applicability of the application.

A favourable international preliminary examination report generally makes the subsequent processing of the national and regional patents before their respective national and regional patent offices run much more smoothly, and there is considerable saving in time, effort and cost to be had by obtaining a favorable international preliminary examination report from the International Preliminary Examining Authority.

  1. AE United Arab Emirates
  2. AG Antigua and Barbuda
  3. AL Albania
  4. AM Armenia
  5. AT Austria
  6. AU Australia
  7. AZ Azerbaijan
  8. BA Bosnia and Herzegovina
  9. BB Barbados
  10. BE Belgium
  11. BF Burkina Faso
  12. BG Bulgaria
  13. BJ Benin
  14. BR Brazil
  15. BW Botswana
  16. BY Belarus
  17. BZ Belize
  18. CA Canada
  19. CF Central African Republic
  20. CG Congo
  21. CH Switzerland
  22. CI Cote d'Ivoire
  23. CM Cameroon
  24. CN China
  25. CO Columbia
  26. CR Costa Rica
  27. CU Cuba
  28. CY Cyprus
  29. CZ Czech Republic
  30. DE Germany
  31. DK Denmark
  32. DM Dominica
  33. DZ Algeria
  34. EC Ecuador
  35. EE Estonia
  36. EG Egypt
  37. ES Spain
  38. FI Finland
  39. FR France
  40. GA Gabon
  41. GB United Kingdom
  42. GD Grenada
  43. GE Georgia
  44. GH Ghana
  45. GM Gambia



  1. GN Guinea
  2. GQ Equatorial Guinea
  3. GR Greece
  4. GW Guinea-Bissau
  5. HR Croatia
  6. HU Hungary
  7. ID Indonesia
  8. IE Ireland
  9. IL Israel
  10. IN India
  11. IS Iceland
  12. IT Italy
  13. JP Japan
  14. KE Kenya
  15. KG Kyrgyzstan
  16. KM Comoros
  17. KN Saint Kitts and Nevis
  18. KP Democratic People's Republic of Korea
  19. KR Republic of Korea
  20. KZ Kazakhstan
  21. LC Saint Lucia
  22. LI Liechtenstein
  23. LK Sri Lanka
  24. LR Liberia
  25. LS Lesotho
  26. LT Lithuania
  27. LU Luxembourg
  28. LV Latvia
  29. LY Libyan Arab Jamahiriya
  30. MA Morocco
  31. MC Monaco
  32. MD Republic of Moldova
  33. MG Madagascar
  34. MK The former Yugoslav Republic of Macedonia
  35. ML Mali
  36. MN Mongolia
  37. MR Mauritania
  38. MW Malawi
  39. MX Mexico
  40. MZ Mozambique
  41. NA Namibia
  42. GE Georgia
  43. GH Ghana


  1. GM Gambia
  2. GN Guinea
  3. GQ Equatorial Guinea
  4. GR Greece
  5. GW Guinea-Bissau
  6. HR Croatia
  7. HU Hungary
  8. ID Indonesia
  9. IE Ireland
  10. IL Israel
  11. IN India
  12. IS Iceland
  13. IT Italy
  14. JP Japan
  15. KE Kenya
  16. KG Kyrgyzstan
  17. KM Comoros
  18. KN Saint Kitts and Nevis
  19. KP Democratic People's Republic of Korea
  20. KR Republic of Korea
  21. KZ Kazakhstan
  22. LC Saint Lucia
  23. LI Liechtenstein
  24. LK Sri Lanka
  25. LR Liberia
  26. LS Lesotho
  27. LT Lithuania
  28. LU Luxembourg
  29. LV Latvia
  30. LY Libyan Arab Jamahiriya
  31. MA Morocco
  32. MC Monaco
  33. MD Republic of Moldova
  34. MG Madagascar
  35. MK The former Yugoslav Republic of Macedonia
  36. ML Mali
  37. MN Mongolia
  38. MR Mauritania
  39. MW Malawi
  40. MX Mexico

December 2014