According to several buyout firms Nielsen is planning to have an IPO. Nielsen is a TV and Internet ratings research company. Nielsen has six sponsors: Alpinvest, The Blackstone Group, The Carlyle Group, Hellman & Friedman, Kohlberg Kravis Roberts (KKR), and THL Partners. The six sponsors are hoping that Nielsen will receive a $21 billion enterprise value according to the Financial Times. Nielsen is expected to make about $1.6 billion in EBITDA this year according to an F.T. source. [FT via NYT]