A system for watermarking data associated with one or more products includes one or more software components that collectively generate an algorithm for creating a particular pattern in data associated with one or more products available from one or more sellers. The data is stored in one or more databases accessible to one or more buyer computers for search queries for data associated with certain of the products. The pattern facilitates identification of a copy of the data and does not substantially affect authorized use of the data by the one or more buyer computers or users associated with the buyer computers. The software components collectively apply the algorithm to the data to create the particular pattern in the data.