It seems, Google Webmasters tools is testing a new feature called “Parameter Handling,” which asks site owner to specify up to 15 parameters in URLs which they want Google to ignore, when crawling and indexing the site. This new option appears in Google Webmaster Tools via Site Configuration > Settings > Parameter Handling. Either way, by allowing webmasters to specify parameters for Google to ignore, webmasters can help Google better identify which URLs they want Google to crawl, index and display in SERPs.