British Telecommunications plc v. Prodigy Communications Corp. was a patent infringement case which determined whether a patent related to communications between central computers and their clients was infringed by Internet service providers through hyperlinks. Judge Colleen McMahon of the United States District Court for the Southern District of New York ruled that Prodigy Communications Corporation had not infringed the patent held by British Telecommunications plc through its use of hyperlinks. On summary judgment, McMahon held that there were substantial differences between British Telecommunications' patent and the method of operation of the Internet. The decision limited patent protection for Internet service providers' use of hyperlinks, protecting the providers from licensing fees