Utilize the input text as a context reference, choose the right relationship between comScore and Rentrak from the options. Options: product/material produced, manufacturer, distributed by, industry, position held, original broadcaster, owned by, founded by, distribution format, headquarters location, stock exchange, currency, parent organization, chief executive officer, director/manager, owner of, operator, member of, employer, chairperson, platform, subsidiary, legal form, publisher, developer, brand, business division, location of formation, creator.

"The merger between comScore and Rentrak signals an important step forward to address the measurement mandate: a call for investment in common GRP and ROI metrics across all platforms, from time shifted viewing to mobile.

Answer: owner_of