Non-patent protection of pharmaceuticals includes regulatory data protection, patent term extension and market exclusivity. In Turkey, although there is no legislation concerning patent term extension and market exclusivity, there is legislation regarding data protection in the pharmaceutical industry. While, regulatory data protection in Turkey is evaluated here in its various dimensions, because of the latest regulation introducing Data Exclusivity into Turkish legislation, Data Exclusivity constitutes the primary interest of this Thesis.This study evaluates the theory, legislation and implementation of regulatory data protection in human medicinal products under the TRIPS regime, in the EU and US, and finally, in Turkey. However, the core of this study is to evaluate the approach that grants exclusive rights on test and other data to the generators of such data for a limited term, which eventually prevents the regulatory authority for a defined period from relying on such data in order to accept the subsequent (generic) authorisation applications. This approach is called Data Exclusivity.TRIPS is the main international instrument that includes a specific provision concerning protection of regulatory data. Developed countries insist on an interpretation of Article 39.3 of the TRIPS Agreement that requires WTO members to establish a Data Exclusivity regime similar to that in force in the U.S. and Europe. However, the negotiating history of the provision clearly suggests that a proposal by the U.S. to incorporate a Data Exclusivity provision into the TRIPS Agreement was rejected by negotiators. In contrast, developing nations assert that Article 39.3 of TRIPS merely mandates WTO members not to disclose the test data to third parties; however they are free to confer marketing authorisation to generic manufacturers at any time by relying on the data already submitted to them.In the EU the total exclusivity term is 10 years, which is divided into an eight-year term and a subsequent two-year term. In the EU, Data Exclusivity period will only extend the monopoly of the originator where it takes an unusually long time for the medicine to be authorised. In the EU, overall exclusivity period granted to a pharmaceutical is lengthened through an EU supplementary protection certificate. Therefore, drugs benefiting significantly from Data Exclusivity are mostly those, which are not entitled to obtain an SPC, or those, which take an extraordinarily lengthy time to secure regulatory approval.As Turkey has established a Customs Union with the EU on the way to full membership, Turkey has come under obligation to provide the same protection that was provided in the EU to the regulatory data, submitted to the authorities in order to obtain marketing authorisation, at the time Decisions 1/95 and 2/95 of the Association Council were taken. At the time when those Decisions were taken Data Exclusivity period was either 6 or 10 years and could be limited with the patent term at the discretion of the member state in concern.The Ministry of Health introduced six-year Data Exclusivity with the adoption of a an amendment in the regulation of licensing of human medicinal products in 2005 which prevents subsequent applicants to benefit from the data in the application dossier of the original manufacturer, through filing an abbreviated application, for six years. Whether the regulatory authority reviews the file of the originator or merely relies on it in evaluating the abbreviated application there is a use of the test data of the originator. However, such a use is not unfair within the meaning of Article 39 of TRIPS and Article 56-57 of the Turkish Commercial Code because there are no dishonest or fraudulent practices involved in such an application unless the generic applicant acquires the test data of the originator by dishonest means such as bribing or trespassing.An equitable and fair solution guided by the philosophy underlying the TIRPS Agreement should balance differing interests and should prevent results which reflect a one-sided assessment of interests. The primary form of protection granted to original products is patent protection. The significant differences in interpretation of Article 39.3 of TRIPS, the existence of patent protection, public health concerns and the lack of any hard data on the extent to which this form of data protection is necessary in order to promote innovation and ensure fair but not excessive commercial returns for an original drug, resulted in some safeguards attached to the implementation of Data Exclusivity. In Turkey, because of the safeguards adopted with the implementation of Data Exclusivity the negative effects on local generic industry and the public healthcare system has been felt less effectively. Finally, abbreviated applications should be regulated through a code enacted by the parliament rather than a Regulation introduced by the Ministry of Health in order to bring clarity into the implementation of regulatory data protection.