Utilize the input text as a context reference, choose the right relationship between 'comScore' and 'Rentrak' from the options.
Options: employer, owner of, platform, brand

Investors and security holders will be able to obtain free copies of the registration statement and the joint proxy statement/prospectus (when they are available) and any other documents filed by comScore and Rentrak with the SEC at the SEC's website at www.sec.gov .
owner of