Overview of the US Patent Infringement Procedure

The US patent infringement procedure is the central mechanism for enforcing patent rights in the United States. While the fundamental questions of patent infringement - such as literal or equivalent use - are also relevant in other jurisdictions, the US system has some peculiarities.

The definition of patent infringement under US law

In the USA, a distinction is made between two main forms of patent infringement:

• Direct infringement: According to 35 USC § 271(a), direct infringement occurs when someone makes, uses, sells, offers for sale, or imports the patented invention without the consent of the patent owner.

• Indirect injury: This includes in particular induced injury and contributory injury.

• In induced infringement (35 USC § 271(b)), the defendant intentionally encourages or assists an infringement by a third party.

• Contributory infringement (35 USC § 271(c)) concerns the supply of components that are specifically designed for the patented invention and have no other substantial use.

A crucial point in US patent infringement law is the concept of equivalent infringement. The “Doctrine of Equivalents” makes it possible to establish patent infringements even if the attacked embodiment does not literally fulfill all the features of the patent claim, but essentially achieves the same function in the same way with the same result.

Infringement and Legality

In US law, the plaintiff bears the burden of proof of patent infringement. The so-called “preponderance of evidence” standard applies. One possible defense for the defendant is to challenge the validity of the patent (invalidity defense). This can be done in addition to or as an alternative to denying the actual patent infringement (non-infringement defense).

The validity of patents is presumed. If the defendant invokes invalidity, it must therefore prove with “clear and convincing evidence” that the patent in question is invalid. This burden of proof is stricter than the “preponderance of evidence” standard that applies to the question of infringement.

In parallel with infringement proceedings, defendants may also resort to Inter Partes Review (IPR) or Post-Grant Review (PGR) before the USPTO to challenge the validity of the patent.

process of a US patent infringement case

A patent infringement procedure in the USA typically takes place in several phases:

1. Filing the lawsuit

The process begins with the filing of a lawsuit in federal court. Since patent law in the United States is regulated at the federal level, federal courts have exclusive jurisdiction.

2nd discovery phase

The discovery phase is a core part of U.S. procedural law. Both parties have extensive opportunities to collect evidence, including:

• Document requests

• Interviewing of witnesses and experts (depositions)

• Expert reports

Discovery is particularly costly and time-consuming, but it allows for a comprehensive investigation of the facts of the case.

3. Markman Hearing (Claim Construction)

A special feature of the US system is the so-called Markman hearing. In this phase, the judge - not the jury - decides on the interpretation of the patent claims. The interpretation of the claims forms the basis for the later determination of infringement or non-infringement.

4. Trial and Judgment

In US patent litigation, the case can be brought before a jury, which ultimately decides whether patent infringement has occurred and what damages are appropriate. In certain cases, the judge can also decide alone, especially in purely legal matters.

compensation and legal consequences

US patent infringement cases are known for their high damages. The patent owner is entitled to reasonable compensation from the infringer. This compensation must be at least as high as a reasonable royalty fee. Lost profits due to the patent infringement can also be recovered. What is considered "reasonable" is judged based on the usual practice in the respective industry and the patent owner's previous royalties.

If the infringer acted intentionally or knowingly, the court can increase the damages threefold.

In exceptional cases, the court can force the infringer to stop further use of the patent or to remove products that infringe the patent from the market (so-called injunction). In most cases, however, the patent holder is only awarded damages.

Economic and strategic considerations

The US patent infringement process is not only a legal process, but also an economic tool. The high costs and risks of the process - especially due to the extensive discovery and the potentially high damages - often lead to settlement negotiations. An early license agreement can be more advantageous for both parties than a lengthy legal dispute.

In addition, patent infringement proceedings play a central role in companies' competitive strategies. By consistently enforcing patent rights, companies can secure their market position and deter imitators.