The Electronic Frontiers Foundation say that “In an important ruling for free speech” the Court of Appeals for the Seventh Circuit had affirmed that a parody of a popular online video "What What (In the Butt) was a clear case of fair use and that the District Court's early dismissal of the claim was correct and that early dismissals can be appropriate.
South Park aired the "What What (In the Butt) in the USA in a 2008 episode critiquing the popularity of absurd online videos. Two years later, copyright owner Brownmark Films sued Viacom and Comedy Central, alleging copyright infringement. Recognising the episode was an obvious fair use, Judge Stadmueller promptly dismissed the case. Brownmark appealed, claiming that fair use cannot be decided on a motion to dismiss, no matter how obvious. Viacom fought back, and the EFF filed an amicus brief in
support, explaining that being able to dismiss a case early in
litigation—before legal costs can really add up—is crucial to protect free
speech and discourage frivolous litigation.
The appellate court agreed, calling the District Court’s decision “well-reasoned
and delightful” adding that the court could ‘properly decide fair use’ at an
early stage …. despite Brownmark’s assertions to the contrary.
The EFF say that the opinion joins a growing body of precedent affirming that it's proper to dismiss some copyright cases early, and that it's possible in appropriate cases to determine whether a use is non-infringing without engaging in lengthy discovery. These rulings are important not only to protect speech, but also in fighting back against copyright trolls.
The EFF point out that trolls depend on the threat of legal costs to encourage people to settle cases even though they might have legitimate defences and citing EFF’s
brief, the Seventh Circuit (Chief Judge Easterbrook and Circuit Judges Cudahy and
Hamilton) seem to have acknowledged the problem.
Brownmark Films LLC v Comedy Partners et al  https://www.eff.org/sites/default/files/Brownmark%20Decision.pdf