Neustar, a provider of real-time information and analytics to telecom, finance and media companies, inked a lease for 23,000 square feet at SL Green Realty’s 100 Park Avenue, sources told The Real Deal. The company, which is publicly traded on the Nasdaq, will consolidate its operations at the 36-story tower. It had previously operated out of two separate locations, including 625 Broadway. It wasn’t immediately clear how much space it held at those two locations.