For years, patent law in the US has been highly problematic. The biggest issue facing the patent world has been the fact that a patent holder, while filing a suit against someone they believe to be infringing upon that patent, could choose the court in which to file. This caused non-practicing entities, or patent trolls, to file in courts that were favorable to their cause.
In the recent past, the Obama administration tried to address the issue by making unrelated changes; namely the way patents can be filed. Rather than first to invent, patent law changed to first to file, meaning that non-practicing entities could file a patent for technology already in the wild, and then file suit in a favorable court.
One case, however, challenged this: TC Heartland v. Kraft Foods Group Brands. This case made it to the US Supreme Court and a unanimous ruling has been issued. That ruling changes the way patent suits can be filed and, more importantly, where those suits can be filed.
Rather than shopping around and filing a full third of all patent cases in a single court, a patent case must now be filed in a court within the jurisdiction in which the defendant is headquartered. This brings patent law more inline with other types of trials, where cases must be brought where the defendant is located, or where a crime has been committed, and not in a court favorable to the prosecution.
This will not entirely solve the issues rampant within the US patent system, but it is a good start.