In the context of the input sentence, determine the relationship between 'comScore' and 'Rentrak'.
Options: platform, developer, owner of, founded by

They may also be obtained for free by contacting comScore Investor Relations by mail at comScore, Inc., 11950 Democracy Drive, Suite 600, Reston, Virginia 20190, Attention: Investor Relations, by telephone at (703) 438-2305, or by going to comScore's Investor Relations page on its corporate web site at www.comscore.com , or by contacting Rentrak Investor Relations by mail at Rentrak Corporation, 7700 N.E.
owner of