Under the terms of the merger agreement, Quadrangle will acquire all of the outstanding common stock of for $15.50 per share in cash.
This represents a premium of approximately 17% over the company's closing share price of $13.28 on June 13, 2008 and a premium of approximately 26% over the average closing share price during the prior 30 days.
The board of directors from Greenfield Online, which owns Ciao Surveys in Europe, has unanimously approved the merger and has recommended that shareholders vote in favour of the merger.
Albert Angrisani, Greenfield Online's president and CEO, said: "Clearly Quadrangle values Greenfield Online's two growing and profitable businesses, Comparison Shopping and Internet Survey Solutions, along with their global leadership position, satisfied clients and talented employees.
"We expect the transition will be positive for our business, our customers and employees, and we look forward to leveraging Quadrangle's expertise in the media, communication and information industries."
Gordon Holmes, managing principal of Quadrangle, said: "Having followed Greenfield Online closely over an extended period, we became increasingly impressed with its international leadership position in online comparison shopping and survey research, as well as its record of strong growth.
"Using our New York and London offices and our new office in Silicon Valley led by Dan Rosensweig, we were able to fully analyze and appreciate the strength of Greenfield's global platform, and determine that it represents an attractive investment opportunity for Quadrangle, consistent with our ongoing focus on the media and communications industry."
The deal, which is expected to close in the late third quarter or fourth quarter of 2008, is being financed by a combination of equity provided by Quadrangle and debt, for which Quadrangle has received financing commitments, and cash on hand at the company.