Buchanan Ingersoll & Rooney’s patent prosecution practice was recognized on the 2012 “Kings of IP” list, an elite roster of firms who represent Fortune 100 companies.

The firm’s handling of patent prosecution matters for Lockheed Martin, Sunoco and Philip Morris earned it a spot on the list.

To find out “who’s hiring whom,” Corporate Counsel magazine combed court filings and tabulated the number of mentions a given firm received. The resulting list examines “one of the most crucial decisions made by corporate legal departments.”