Google has joined with BlackBerry and other tech firms to request US regulators to pay greater attention to ‘patent trolls’, which they say may undermine patent peace.

The tech majors have requested the regulators to probe whether some competing firms violate antitrust laws by roping in companies to file patent-infringement cases against other companies.

Google, BlackBerry, EarthLink and Red Hat have submitted comments to the US Federal Trade Commission and Department of Justice saying that there is a rise in infringement lawsuits.

The companies said ‘patent trolls’, or patent assertion entities (PAEs), are filing four times as many cases today as in 2005 and PAE lawsuits now account for 62% of all recently filed patent litigation.

PAE claims cost US firms $29bn in 2011 and $80bn when accounting for all costs in direct and indirect ways.

Google and BlackBerry said: "We are also concerned with, and suggest that the agencies should seriously examine, the outsourcing of patent enforcement by operating companies – companies that develop technology and sell products – to PAEs and the competitive implications of such activities."

"So-called ‘privateering’ amplifies the threat to innovation and competition already posed by PAEs," the companies said.

Google senior competition counsel Matthew Bye said privateering lets a company split its patent portfolio into smaller sub-portfolios stacked on each other, increasing the number of entities a firm must negotiate with and multiplying licensing costs.

"This behavior unfairly raises competitors’ costs, ultimately driving up prices for consumers. It also undermines incentives for companies to work together towards "patent peace" through good-faith negotiation and cross-licensing," Bye said.

Google, BlackBerry, EarthLink, and Red Hat requested that the FTC and DOJ conduct an inquiry into the relationship between PAEs and operating firms.