Patent holder A has a patent on an innovative water outlet valve for fittings that reduces water consumption by up to 40% through a special flow control system without the user noticing any loss of pressure. This valve can be used in standard fittings and is particularly attractive for hotels and commercial kitchens as it enables significant savings.
Two competitors enter the market: B, a small regional craft business, and C, an international manufacturer of sanitary technology. Both incorporate the patented flow technology into their own fittings without asking A for a license.
A notices the infringements but initially decides against legal action. In B's case, it is hardly worth it economically: the company is small, sells only a few fittings, and even a lawsuit for damages would hardly bring in any revenue. In addition, A itself is in a difficult economic situation and is reluctant to incur high legal costs.
B uses the technology for about three years but then ceases production completely. C, on the other hand, uses the patented outlet valve permanently in its series production, sells thousands of fittings per year, and thus continuously increases its profits.
A few years later, A is in a better financial position again. He wants to take action against B and C for injunctive relief and damages.
The statute of limitations for claims is a fundamental principle of civil law and also applies in patent law. The legislator requires that legal claims be asserted within a certain period of time in order to ensure legal peace and security. In Austrian patent law, claims arising from patent infringements generally become time-barred after three years, beginning with the date on which the patent holder became aware of the infringement and the identity of the infringer. In any case, the statute of limitations expires 30 years after the date of the infringement, regardless of the patent holder's knowledge. This means that no claims can be asserted after the expiry of these 30 years, even if the patent holder only learns of the infringement at a later date.
As soon as A notices that B and C are infringing his patent, the three-year limitation period begins to run – provided that he is aware of the specific infringement and the identity of the respective infringer. For B, who has only been producing for three years, the claims could therefore be time-barred long before A asserts them in time.
Even if A had no knowledge of the infringements, all claims would be time-barred at the latest 30 years after each individual production or delivery by B and C.
The right to injunctive relief in patent law does not expire simply because a previous infringement is already time-barred. Each new or continued infringement is treated legally as a separate act. This also means that the three-year limitation period starts to run again in each case. Even if claims for past infringements are time-barred, the patent holder remains entitled to take action against current and future infringements. The right to injunctive relief is therefore not “exhausted” by past infringements, but continues to protect the patent holder against further infringements of his rights.
There is no longer any current right to injunctive relief against B, who ceased production after three years – although his previous infringements may still have given rise to monetary claims, there is no longer any claim for injunctive relief because there is no longer any threat of new infringements.
Since C continues to use the technology to this day, he is constantly committing new acts of infringement. Each of these acts gives rise to a separate right to injunctive relief, so that A can successfully take action against C at any time, despite the possible statute of limitations on older infringements. The right to injunctive relief therefore has a continuous effect and permanently protects A against continued infringements of his patent.
The monetary claim (e.g., for damages or surrender of the infringer's profits) arises in each case with the specific act of infringement. This act also marks the start of the 30-year maximum limitation period.
In addition, the three-year limitation period begins at the point in time when the patent holder becomes aware of the infringement and the identity of the infringer. This means that older, long-known claims may become time-barred, while newer or initially hidden infringements can still be pursued.
Since A was aware of all acts of infringement, the three-year limitation period applies. This begins to run as soon as A becomes aware of the respective infringement and the infringer. Since A knew early on that B was using his technology, these claims may already be time-barred if he did not sue within three years. In the case of C, on the other hand, who continues to use the patented technology, new claims arise constantly, which A can still assert today. A can continue to assert claims for damages for acts committed within the last three years.
Austrian patent law clearly applies the principle that the mere inaction of the patent holder does not give the infringer the right to continue using the patent. The individual claims that arise do become time-barred if the patent holder fails to act. However, an infringer cannot claim that the patent holder has tolerated their use for years and that they have thereby acquired their own right of use, i.e., that they have “acquired” a right of use. Such an institution is referred to as forfeiture in German law and Austrian trademark law, but does not exist in Austrian patent law. The only barrier therefore remains the statute of limitations, which merely extinguishes individual claims of the patent holder without granting the infringer a positive right to continued use.
Even if A has remained inactive for many years and has not taken action against C's continued patent infringements, this does not give C any right to continue using the patented technology. Even inactivity for ten or more years does not result in C obtaining its own right of use under Austrian patent law.
With the expiry of a patent, the basis for all claims that are directed toward the future ceases to exist. This includes, in particular, the right to injunctive relief. Since the patent no longer provides protection, there can be no future infringements that would need to be prohibited. The right to injunctive relief thus becomes irrelevant.
Assuming that A's patent expires due to the expiry of the maximum statutory term, any basis for a right to injunctive relief automatically ceases to exist. Since the expiry means that there is no longer any exclusive right, there can be no future patent infringement that would need to be prohibited. Any court injunction already issued loses its effect at this point because it is based on a property right that no longer exists. From this point on, the previously protected actions are freely permissible and patent infringement is no longer legally possible.
Monetary claims such as damages or surrender of the infringer's profits are generally not affected by the expiration of the patent. These claims arise at the time of the respective infringement and remain valid even after the patent has expired. They can therefore continue to be asserted as long as they are not time-barred. The expiration therefore only has an effect in the future, while financial claims from the past remain unaffected.
Although A's patent has now expired, the monetary claims from the past remain. A can continue to claim damages or surrender of the infringer's profits from C, who has used the patented technology continuously until the end of the term of protection. However, if A became aware of the acts of infringement, the statute of limitations may already have expired.
