Even if the company could afford the legal fees, the board of directors will probably nix it and say they are better off using the money for research and development, Hayes noted.

Under a contingent fee arrangement, the company might agree to pay the expenses, which could amount to $1 million over four years, and share a percentage of the recovery.

Anthony Froio, a managing partner at Robins Kaplan Miller & Ciresi, said companies are increasingly looking for alternative fee structures.

If you file a patent infringement case these days, you better be prepared to litigate to the end. More and more clients are calling me and saying 'We are no longer able to afford this case. Would you look into taking it on a contingent fee basis?' he said.

Small businesses, inventors and institutions of higher learning, such as teaching hospitals, couldn't possibly afford to take on patents offensively, never mind on an hourly rate. We give them a significant option on the fee, he said.

Sunstein, who has spoken at an ABA conference on this subject, said contingent fees might be particularly attractive to a company that holds a patent, but it is not part of its core business.

Why should it spend $3 million for a patent peripheral to its business if the patent isn't affecting its profitability? he asked.

Another scenario in which a contingent fee arrangement might make sense is where a small company with decent revenues wants to assert a patent against a competitor whose infringement is taking away