Online reviewer Yelp Inc. is the latest Northern California tech firm adding a large office in the Merchandise Mart, where it is expected to move into more than 50,000 square feet by next year.

http://www.chicagobusiness.com/realestate/20140806/CRED03/140809893/with-big-lease-is-yelp-plotting-a-hiring-binge-at-merchandise-mart