Civil procedure
Preliminary Injunction
A preliminary injunction is a court order requiring a party to do or stop doing something while the lawsuit is pending.
Unlike a TRO it follows notice and a hearing, and it lasts until final judgment. Because it hands out real relief before anyone has proven a case, the standard is demanding: likelihood of success, irreparable harm, a favorable balance of equities, and the public interest.
The ruling often decides the war. An injunction that stops a product launch or a merger changes the parties' leverage so much that the case settles, which is also why these orders are immediately appealable.
It also produces an unusually informative record. Because the court has to explain its findings on likelihood of success, the opinion often reads like an early ruling on the merits, which is why both sides treat the hearing as a dress rehearsal for trial.
How it appears on a docket
ORDER granting 24 Motion for Preliminary Injunction. Defendant shall cease use of the disputed mark pending trial. Notice of appeal filed 7/2/2025.
Governing rule
Fed. R. Civ. P. 65(a); 28 U.S.C. Sec. 1292(a)(1)
Related terms
- Temporary Restraining Order — A temporary restraining order, or TRO, is a short emergency order freezing the situation until the court can hold a real hearing.
- Interlocutory Appeal — An interlocutory appeal is an appeal taken before the case is over, from an order that does not end the litigation.
More on civil procedure
See this term in a real case
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