With regard to the dates of application of the TRIPS Agreement, a distinction is made between the least developed countries and developing countries, and also between countries with or without a system of patent protection for pharmaceuticals at the time of the expiration of the general transitional period (31 December 1999).
8.1 Industrialized countries
The TRIPS Agreement has been applicable since 1996.
8.2 Transitional period for developing countries.
By the year 2000, they should have introduced into their national regulations on intellectual property the various rules of the Agreement they accepted by joining to the WTO.
However, the Agreement grants an extra five year transitional period for those countries that did not issue patents before 31 December 1999. In this case, the Agreement grants them a total transitional period of ten years (i.e. until 2005)
8.3 Transitional period for least-developed countries
Least-developed countries are given 11 years, (i.e. until 2006), with a possible extension, to harmonize their regulations with the new international obligations.
Countries should have adapted/modified their national legislation on Intellectual Property Rights (such as patents) before the end of the applicable transition period.