The Center for Public Integrity has published an interesting article, Influencing the IRS: Nearly 500 Companies Lobby the Tax Agency:

Nearly 500 companies and organizations have reported lobbying the IRS between 1998 and 2004, putting the nation’s revenue collector among the top 30 most frequently lobbied federal agencies, according to a study of federal lobbying records by the Center for Public Integrity. In fact, more companies and organizations reported lobbying the IRS than the Navy, the Joint Chiefs of Staff and the President of the United States combined.

(Thanks to reader Ben Cunningham for the tip.)