From the Electronic Frontier Foundantion:

In OPG v. Diebold, [337 F. Supp. 2d 1195 (N.D. Cal. 2004)(pdf)] a California district court has determined that Diebold, Inc., a manufacturer of electronic voting machines, knowingly misrepresented that online commentators, including IndyMedia and two Swarthmore college students, had infringed the company's copyrights. EFF and the Center for Internet and Society Cyberlaw Clinic at Stanford Law School sued on behalf of nonprofit Internet Service Provider (ISP) Online Policy Group (OPG) and the two students to prevent Diebold's abusive copyright claims from silencing public debate about voting.

Diebold sent dozens of cease-and-desist letters to ISPs hosting leaked internal documents revealing flaws in Diebold's e-voting machines. The company claimed copyright violations and used the DMCA to demand that the documents be taken down. One ISP, OPG, refused to remove them in the name of free speech, and thus became the first ISP to test whether it would be held liable for the actions of its users in such a situation.

In his decision, Judge Jeremy Fogel wrote, "No reasonable copyright holder could have believed that the portions of the email archive discussing possible technical problems with Diebold's voting machines were proteced by copyright." In turn, Diebold had violated section 512(f) of the DMCA, which makes it unlawful to use DMCA takedown threats when the copyright holder knows that infringement has not actually occured.

Diebold subsequently agreed to pay $125,000 in damages and fees.

EFF's page providing all the legal documents in OPG v. Diebold is here.

Google's policy on DMCA takedown notices is set forth here.