In September, I wrote that the America Invents Act’s (“AIA”) main impact upon patent litigation would be the new joinder rule prohibiting suing multiple, unrelated defendants in a single case. In the two weeks between the Senate’s passage of the AIA and President Obama signing it into law, patent trolls flooded the federal courts with what we all expected was the final set of huge multi-defendant cases. After President Obama signed the AIA, multi-defendant cases as we knew them (at least a trial) appeared dead.

But there has been an interesting phenomenon since September 16, some trolls have been amending complaints in existing multi-defendant cases to add dozens of new defendants. It is too soon for the motions to dismiss for improper joinder to have been filed. But I expect we will see a lot of those motions. And those motions should be successful. There was no clause exempting existing cases from the new joinder rule, and the joinder change was one of the immediately enacted portions of the AIA.

Of course, this issue is somewhat academic. As I discussed in August, the new joinder rule is more of a speed bump than it is a true barrier to entry. And the filings since September 16 have proven my analysis. Trolls continue filing what amount to multi-defendant cases. They just file them in separate cases on the same day or within a few days of each other, identifying the cases as related so that they likely go to the same judge. And preliminary indications are that judges are doing the only sane thing — consolidating the cases for discovery. The real test will be when a judge has to have 100 individual trials on similar, but not identical products, as required by the AIA.