As an inventor, few situations can be more frustrating than seeing a competitor utilize your invention without permission. After all, you invested time, money, and energy into creating your invention.
When your patent is being infringed, time is of the essence. You could quite literally be losing sales on a daily, if not hourly, basis. While a full-blown trial can take years, federal procedure fortunately provides a legal mechanism for you to stop the infringer, at least in some instances.
Most civil lawsuits seek money damages, meaning a judgment from the court that the defendant owes a certain number of dollars to the plaintiff based upon his or her conduct. But in some cases, courts can do more than issue judgments for money damages. They can also issue injunctive relief.
An injunction is essentially a judicial order that a party must do, or refrain from doing, something.
When would you seek an injunction in court? Imagine, for example, that your neighbor is beginning to perform construction on the foundation of her house, which is likely to rock your own house's foundation. Or imagine that a tabloid magazine is about to publish knowingly false and damaging photos of you. Or imagine that a critical vendor to your business has told you that it intends to stop producing essential materials, which would breach its contract to you. In all of these cases, you wouldn't want to wait around to be paid damages. You would want a court order directing that the other party stop what it's doing.
Needless to say, injunctions are also critical in situations of intellectual property theft. Whether the intellectual property in question is a patent, trademark, or copyright, you will want a judicial order commanding that the defendant cease its infringing conduct. (You may also want money damages for the infringement that has occurred so far).
As described above, you can file a lawsuit seeking injunctive or equitable relief. But like any other type of lawsuit, you must actually win the case at trial (or by motion) before the court will actually award you the relief that you seek. So if you want a permanent injunction that prohibits someone from doing something, you would need to win on the merits.
But litigation can take years. Even filing a motion for a preliminary injunction, with time for an opposition brief by the defendant and a hearing, can take weeks. Given that, a plaintiff sometimes needs a way to maintain the status quo to prevent a defendant from doing something immediately before the parties can engage in briefings and hearings during the litigation.
A temporary restraining order (TRO) is different from either a permanent injunction (obtained by winning a lawsuit) or a preliminary injunction (obtained through briefings and arguments from both sides).
Under Federal Rule of Civil Procedure 65(b): "The court may issue a temporary restraining order without written or oral notice to the adverse party or its attorney only if: (A) specific facts in an affidavit or a verified complaint clearly show that immediate and irreparable injury, loss, or damage will result to the movant before the adverse party can be heard in opposition; and (B) the movant's attorney certifies in writing any efforts made to give notice and the reasons why it should not be required."
This basically means that a patent holder must establish that the particular facts of your case show that the defendant's infringement will result in "immediate and irreparable injury, loss, or damage" before there is a chance for a hearing or briefing from both sides. You will probably need to establish that your lawsuit has a strong likelihood of success, a need for immediate relief.
Note that TROs are intended to preserve the status quo, and courts will usually allow them to last only so long as is necessary to hold a hearing and allow both sides to argue their position. While TROs are not granted lightly in patent disputes, be aware of this tool in your arsenal. If you believe that you need a TRO, you should immediately speak with a qualified patent attorney.