In June 2004 JibJab creators of the fantastically popular "This Land" animated parody lampooning John Kerry and George Bush were threatened with a copyright lawsuit for the soundtrack which was based on Woody Guthrie's "This Land is Your Land." The threat came from Ludlow Music Inc. the music publisher that claimed to own the song. JibJab sued Ludlow in federal court in July 2004 seeking judicial confirmation that JibJab's work was a protected "fair use" and did not infringe Ludlow's copyrights. EFF served as counsel to JibJab.
During the course of the litigation EFF discovered that the copyright to "This Land is Your Land" expired in 1973 putting the song into the public domain. Woody Guthrie wrote his classic American song in 1940 when the copyright laws granted a copyright term of 28 years renewable once for an additional 28. The initial copyright term was triggered when Guthrie sold his first versions of the song as sheet music in 1945 (this sheet music is available in the Guthrie archives at the Library of Congress; EFF has posted a copy). The copyright on the song then ran out when Ludlow failed to renew its registration in 1973. (Ludlow which apparently was not aware of Guthrie's 1945 sheet music distribution believes its copyright remains valid. We've posted all the evidence so you can decide for yourselves.)
JibJab and Ludlow ultimately settled the litigation. As part of the settlement of the case JibJab remains free to continue distributing the "This Land" animation without further interference from Ludlow.