According to the barcode system, the trademark owner of the product (regardless of where or by whom) is responsible for assigning the barcode number to the product. However, as in the cases stated below, the trademark owner of the product may also be the manufacturer, distributor, importer or retailer of the product.

If the manufacturer sells the product he/she produces under his/her own or trademark title

If the importer/wholesaler sells the product produced in any country under its own brand name or if the importer/wholesaler has changed the product (for example, changes in the product packaging)

If the retailer sells the product produced in any country under its own trademark title.

Barcode applications are made on a company basis. The company accepted to membership creates barcode numbers for the product types with the GS1 Company Prefix allocated.

After receiving GS1 Company Prefix by applying the TOBB-GS1 Turkey, according to the company 7, 8, 9, 10, 11 or 12-digit GS1 Company Prefix is allocated. Next, the company has to create a product number for each type of product as provided in the table below.

The identification numbers given after the product number is given must be symbolized with a barcode on the product package. If the barcode of a product is to be printed in large numbers, the cheapest and easiest method is to obtain barcode master film.

Each member of TOBB-GS1 Turkey has to submit the Trade Registry Gazette indicating the change of address and title if made durşng the membership with a letter.

In address and name changes, the company prefix allocated to TOBB-GS1 Turkey members is not allowed to be granted to other natural or legal persons. But they can transfer their membership if approved by TOBB-GS1 Turkey.

After the number of products that can be numbered with a prefix is filled, the companies that used all product numbers that can be created with the existing GS1 company prefixes, has to submit the Income Statement including the turnover of the previous financial year and the receipt showing that the fee determined according to the previous financial year turnover of the company is deposited for obtaining additional numbers.

The companies member to the TOBB-GS1 Turkey have to deposit the annual contribution to the bank account of TOBB-GS1 Turkey in September each year. The annual contribution is not paid in the year the firm becomes a member. Annual contribution amount for each year is determined by the TOBB-GS1 Turkey and announced in writing to the member firms. For being dully informed about the annual contribution announcements, the member companies have to notify their current address to the TOBB- GS1 Turkey.

In order to make the GS1 System a global development and to be used as a single system all over the world, GS1 US (USA) and GS1 Canada (Canada) have announced that all US and Canadian retail companies could read GTIN-8 (EAN-8) and GTIN-13 (EAN-13) barcodes as of January 1, 2005. This initiative, called "Sunrise 2005" (Sunrise 2005), was announced in 1997.

However, some US and Canadian companies still require their partners to use the UPC barcodes. In these special cases, the companies member to the GS1 System, may apply to TOBB-GS1 Turkey for the allocation of a UPC number different from the GS1 System barcode numbers and TOBB-GS1 Turkey can assign this number through GS1 US (United States). The applicant company for the allocation of the UPC number,  should apply to TOBB-GS1 Turkey  with a letter requesting the UPC number assignment and a letter from the US or Canadian Company evidencing their such requirement and shall pay the fee determined by the TOBB Board for UPC number assignment.

When a barcoded product is decided to be removed from the market, the number of this product cannot be used for another product for 4 years (48 months). After this period, the same number can be used for another commercial product. The 4-year period when the number cannot be used is calculated starting from the last date the product is offered to the distribution channel. In textile products, the number given to a product can be reused after 30 months.