Evercore negotiating to buy equities research firm ISI E-mail Tweet Facebook Google Plus Linkedin Share icons by Tom Huddleston, Jr. @FortuneMagazine August 1, 2014, 4:04 PM EDT Investment banking firm Evercore Partners is negotiating to pay more than $400 million for closely-held International Strategy & Investment Group in what would be its biggest acquisition ever,Bloomberg reported. Evercore’s stock fell 8.1% Friday to $50.13 after news leaked about the potential merger. Evercore plans to issue 8 million shares of its own shares to acquire the New York-based stock market research firm, according to Bloomberg, which cited anonymous sources. The majority of Evercore’s business is based on advising companies in M&A matters, but the boutique firm has been expanding into other areas and adding ISI’s equities research services, which would help boost Evercore’s stock underwriting business. If a deal is reached, ISI would be merged into a new unit with Evercore’s equities arm, with ISI founder Ed Hyman serving as chairman of the new unit, according to reports.