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.
Refer to the input text as context and select the correct relationship between 'Equinix' and 'data center' from the available options.
Options: product/material produced, creator, parent organization, manufacturer