In 2018, a patent holder learns that a competitor is using his patented packaging machine on a large scale. He initially takes no action and only files a lawsuit in 2023.

Question: Are his claims already time-barred after more than three years have passed?

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A manufacturer has been using a patent-protected welding process since 1990. However, the patent holder only learns of this use in 2022 and wants to take action against it.

Question: Can he still sue despite his lack of knowledge, or has the 30-year maximum period already expired?

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Three Violations

A competitor repeatedly manufactures products based on the same patented design in 2019, 2021, and 2023. The patent holder was aware of these actions.

Question: Can the patent holder still assert a claim for injunctive relief for the later manufacturing acts in 2025?

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The patent on an innovative coating technology expires in 2022. A competitor produced the coated parts continuously from 2020 to 2023.

Question: Does the patent holder still have claims based on patent infringement even after the patent has expired?

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A patent holder observes that a competitor has been using his patented system for over ten years, but does nothing about it. The competitor claims that this long period of tolerance has given him his own right.

Question: Does the mere inaction of the holder give rise to the infringer's own right of use?

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In 2019, a court issues an injunction against an infringer B. Two years later, in 2021, the patent on which the injunction was based expires. B resumes production of the goods that were prohibited by the injunction.

Question: What consequences must B fear?

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A patent holder has known since 2019 that someone is using his technology, but is only able to identify the specific infringer in 2022.

Question: When does the limitation period end?

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