Nielsen could be the next big leveraged buyout, sources say

Nielsen could be the next big leveraged buyout, sources tell CNBC.

Potential bidders could be Hellman & Friedman with Blackstone, or Goldman Sachs Private Equity with Advent International, the sources say. The market research firm, which had its initial public offering in 2011, has been quietly pursuing a take-private deal and a round of bids was due in January, the sources said.

Any deal would follow an $11 billion buyout announced earlier this week for Ultimate Software Group, which agreed to be acquired by Hellman & Friedman. Ultimate is a maker of cloud-based human resources management software.

A take-private of Nielsen could fetch $10 billion, about the same as a previous buyout more than a decade ago by Blackstone and a group of big private equity firms, including Carlyle, KKR and Hellman & Friedman.

Last year, Elliott Management took a sizable stake in Nielsen and pushed for a sale, and Nielsen said in September it had hired bank and legal advisors to explore strategic alternatives. The company named a new CEO, David Kenny, who came on board in December, and after that it began meeting with various private equity firms.