Sony Music's publishing unit Sony/ATV has begun an auction to sell off the publishing rights to over 30,000 songs in the Virgin Music, as well as Famous UK, song catalogs. Sources tell Reuters non-disclosure agreements were sent out last week to over 20 potential bidders, which included Warner Music Group as well as private equity firms such as Thomas H. Lee Partners.

Reuters' sources expect the value of the catalogs to come in around $150 million. The sale of the catalogs is one of Sony/ATV's concessions to regulators in exchange for the recent acquisition of EMI Music Publishing for $2.2 billion.

The Virgin Music and Famous UK catalogs include rights to a number of hit songs from Lenny Kravitz, Iggy Pop, The Goo Goo Dolls, Culture Club and more.