This would make it resemble a kind of class action suit, with the plaintiff suing a large number of defendants, all with substantially identical facts being considered. (slaw.ca)
The judge noted that this was especially an issue because a growing number of defendants had been showing up for trial wearing glasses. (legaltimes.typepad.com)
A second spike, immediately prior to the effective date of the AIA in late 2011, correlates with patent holders» last chance to sue large numbers of defendants in a single case. (lexmachina.com)