In all likelihood, President Obama will sign the Leahy-Smith America Invents Act into law on Friday, September 16, 2011. There are a few issues that folks may want to consider before-hand.
Best Mode: On the date of enactment, failure of best mode will no longer be a basis for adjudging a patent invalid or unenforceable. However, the new provision only applies to lawsuits filed on or after the enactment date. Thus, a declaratory judgment action filed today could still rely on best mode as the basis for invalidity.
Dis-Joinder: A second litigation-focused issue that goes into force on the date of enactment is the new dis-joinder provision. Section 19 of the Leahy-Smith AIA bars a plaintiff from suing multiple defendants in a single lawsuit if the only justification for the joinder is that all defendants are alleged to have infringed the same patent. The law would also bar a court from consolidating cases for the same purpose absent waiver from the multiple defendants. The idea behind the provision is simply to raise the litigation costs of non-practicing entities who allege that their patents are being infringed by a broad spectrum of corporate defendants. The law applies to all lawsuits filed on or after the bill's enactment date. Thus, if President Obama signs the bill into law on Friday, a plaintiff may still file a multi-defendant lawsuit today or tomorrow.