"The New York Times" has complained that the caching of their content during a web crawl, a feature utilized by search engines including Google Web Search, violates copyright. Google observes Internet standard mechanisms for requesting that caching be disabled via the robots.txt file, which is another mechanism that allows operators of a website to request that part or all of their site not be included in search engine results, or via META tags, which allow a content editor to specify whether a document can be crawled or archived, or whether the links on the document can be followed. The U.S. District Court of Nevada ruled that Google's caches do not constitute copyright infringement under American law in "Field v. Google" and "Parker v. Google".