According to the report, the IPO could grow as large as $750 million, though the newswire's sources disagreed about Dunkin's valuation. They did agree that talk of an IPO remains in preliminary stages and that plans could change. "We do not respond to rumors or speculation. We are focused on operating our business and helping our franchisees drive revenues and profits at their restaurants," Dunkin' Brands said in a statement. Dunkin' Brands operates Dunkin' Donuts coffee and donut stores, as well as Baskin-Robbins ice cream shops. Dunkin' opened 574 net new locations around the world in 2010, generating system-wide global sales of $7.7 billion, up more than 20% year-over-year from global sales of $6.4 billion in 2009. "Private equity firms have their own shareholders, and the fundholders are screaming for profits. So it becomes a financial imperative for these firms to try and monetize these investments by bringing them public,'' David Menlow, founder of research company IPOfinancial.com, told Boston.com, referring to recent news of a potential IPO for Zipcar.