US Patent 8131861 Method for cross-domain tracking of web site traffic

Web traffic reporting methods that rely upon third-party cookies suffer in accuracy when those tracking cookies are frequently refused by web users or deleted once they have been accepted. The invention described herein circumvents this problem by employing first-party cookies instead. This is accomplished by a client-side script that maintains the first-party cookie (as placed by the web site in question) and sends a site-maintained visitor ID to a tracking service for analysis. The effect is to improve the accuracy of traffic statistics that rely on that cookie.