Utilize the input text as a context reference, choose the right relationship between Equinix and data center 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.

Earlier this year, $14.7 billion cap Equinix received its formal IRS REIT approval, eclipsing $9.4 billion Digital Realty Trust, Inc. (NYSE: DLR ) as the largest publicly traded data center REIT, calculated by market cap.

Answer: product_or_material_produced