The big three video game console makers ( or platform providers ) each licensed third parties to develop software for use with their respective game-playing systems. Typically the software developer submitted a prototype for evaluation and approval that included all art work to be used in connection with packaging and marketing of the product. Many third-party developers used contract manufacturing sources in Mexico. The platform providers usually retained the right to limit the number of games and approve timing of release under manufacturing and licensing arrangements. Home video game production was based on estimated demand for each specific title, with on-hand inventories depending on seasonal variations in demand during the market life of as specific game title. At the time a newly developed game was approved for manufacturing the developer had to provide the platform manufacturer with a purchase order for that product and an irrevocable letter of credit for 100 percent of the purchase price. Initial orders generally required 30 to 75 days to produce depending on the platform. Reorders of cartridge-based products generally required approximately 50 days to produce, while reorders of CD-ROM-based platforms took only 14 days. Sipping of orders required an additional 3 to 10 days, depending on the mode of transport and location of the software producer.