Jones Day, the United States' largest law firm, is threatening a parody website with litigation because of its use of the corporate logo deriding the firm.

"I write on behalf of Jones Day, a law firm with over 2500 lawyers in offices on five continents, regarding your unauthorized use of Jones Day's service mark on the website www.kevynorr.com ..." begins the letter from firm partner Robert Ducatman to the anonymous blogger.

The Electronic Frontier Foundation, which has come to the assistance of the blogger this week, said Jones Day's actions are one of several in which companies "have improperly" demanded that critics stop using their marks.

"The wise thing for them to do is simply accept somebody said something mean about them on the Internet and move on," EFF staff attorney Daniel Nazer said in a telephone interview Friday.

Ducatman did not respond for comment. But in his June 10 letter, he told the blogger that "Your conduct will be closely monitored."

Law360 in March announced that Jones Day was the biggest US law firm in terms of the number of attorneys, with 1,739. Greenberg Traurig came in second, with 1,558.

The parody site pokes at a former Jones Day partner, Kevyn Orr, who is serving as the emergency financial manager for the financially strapped city of Detroit. The site says Detroit's finances are being reorganized for the betterment of banks, not the public.

Nazer, in a letter to Jones Day, asks Ducatman to lighten up.

"The website fiercely criticizes Kevyn Orr, Jones Day, and other individuals and corporations that our client believes have acted against Detroit's best interests," Nazer wrote (PDF). "The placement of the Jones Day mark—under the tag line: 'Detroit's Economic Coup D'etat has been brought to you by'—is an obvious parody of corporate sponsorship."

Nazer added that "It is well-setled that the First Amendment fully protects the use of trademarked terms and logos in non-commercial websites that criticize and comment upon corporations and products."