A method for determining a warranty start date for a product has steps of determining a warranty start event and generating a warranty start date after occurrence of the warranty start event. The timestamp may be generated through a query to a time server on a network connected to the product. Preferred examples of warranty start events comprise first use by the user, and production of a specified cumulative quantity of product output. The warranty start event as well as the generated warranty start date are preferably stored on a memory internal to the product.