In addition to leasing towers downtown and in The Domain — often called Austin's second downtown — Facebook is taking part of a building at this sprawling suburban business park near Tech Ridge where 500 3M employees are about to move in. Facebook and 3M are just a couple of the Fortune 500 companies fond of the Parmer Innovation Center, which has nearly 900,000 square feet under construction. Facebook is taking the space off the hands of Blue Apron.