Private equity industry accused of collusion during buyout boom A series of documents released by a Boston judge are part of a lawsuit investors have bought against Bain, KKR, Blackstone, Carlyle and other private equity firms. The investors allege that the private equity firms agreed not to compete on 19 deals, including the acquisitions of US hospital owner HCA, retailer Neiman Marcus and radio company Clear Channel Communications. Bain was part of a consortium, alongside KKR, that paid $32bn (20bn pounds) for HCA in 2006. In one of the emails, a KKR executive, asked the "industry to step down on HCA," according to the complaint. The lawsuit, first filed several years ago, alleges that the consortium was allowed to buy HCA at a "suppressed price." Another email released this week relates to the $17.6bn deal in 2006 for US semiconductor maker Freescale, which was acquired by a consortium including Blackstone and Carlyle. The lawsuit alleges that Blackstone told KKR that it would compete for HCA after a consortium, including KKR, entered its own bid for Freescale. KKR withdrew its bid. "We would much rather work with you guys than against you guys," Tony James, the president of Blackstone, wrote in an email to KKR co-founder George Roberts, according to the suit. Together we can be unstoppable but in opposition we can cost each other a lot of money. Although Mr Romney left Bain before the alleged collusion, the release of the emails is unlikely to be welcomed by the Republican candidate. President Barack Obama's campaign has spent millions of dollars trying to paint Mr Romney, whose fortune is estimated at about $250m, as a rich financier who does not understand the pressures faced by millions of Americans. All the defendants in the case deny the charges. "They (the plaintiffs) neither identify any direct evidence of an actual agreement among these 17 defendants to fix the market for large LBOs not allege circumstantial facts that support the plausability of such a conspiracy," the defendants said in the court filing.