As competitors for online real estate listings, Trulia and Zillow knew each other well and even had some of the same institutional investors. That put a premium on communicating the deal’s progress and proposed benefits, says Wilson Sonsini Goodrich & Rosati’s Michael Ringler, who advised Trulia.

“Shareholders in just one company might not value the synergies that were important to shareholders of both companies,” he says. “We were always mindful that there were different shareholder constituencies.”