The fast spreading of electronic business-to-business procurement systems has led to the development of new standards for the exchange of electronic product catalogs (e-catalogs). E-catalogs contain various information about products, essential is price information. Prices are used for buying decisions and following order transactions. While simple price models are often sufficient for the description of indirect goods (e.g. office supplies), other goods and lines of business make higher demands. In this paper we examine what price information is contained in commercial XML standards for the exchange of product catalog data. For that purpose we bring the different implicit price models of the examined catalog standards together and provide a generalized model.