Risks of using marketplace complaint systems to enforce IP rights
In April 2026, the Higher Regional Court of Düsseldorf ("Court") ordered a kitchen appliance manufacturer to pay approximately EUR 36,000 in damages after it filed unjustified patent infringement notifications with a major online marketplace provider, resulting in a competitor's product listings being blocked. The case raises important questions about the limits of using marketplace complaint systems to enforce intellectual property rights.
Background
The plaintiff is a seller of kitchen appliances and accessories, distributing its products through a major online marketplace. The defendant, a competing kitchen appliance manufacturer, filed infringement notifications through the marketplace's complaint system, alleging that the plaintiff's products violated several of its patents. Following these notifications, the marketplace blocked the plaintiff's product listings, leading to the plaintiff being unable to sell the affected products through the platform for several weeks.
The plaintiff sought preliminary injunctions against the defendant, which it obtained, and ultimately brought a claim for damages and injunctive relief.
Positions of the parties
The plaintiff argued that the defendant's notification constituted a targeted obstruction within the meaning of the German Act Against Unfair Competition. On this basis, the defendant was obligated to cease and desist and pay damages, since the plaintiff had been prevented from distributing its products through the online marketplace even though those products did not infringe the defendant's patents.
The plaintiff further argued that the defendant must have been aware that the online marketplace does not carefully review whether an infringement has occurred and instead blocks listings without examination to avoid liability as a platform operator under the Digital Services Act. Aside from unfair competition law, the plaintiff argued that the defendant was also liable under general tort law for injunctive relief and damages, having acted negligently "at the very least".
The defendant argued that the plaintiff's claims for injunctive relief and damages were unfounded, contending that the notifications in question did not constitute an unlawful interference with the plaintiff's business and should not be treated as a cease-and-desist letter, but rather as a request for clarification.
Finally, the defendant claimed that the temporary blocking of the plaintiff's products did not significantly impair consumers' ability to purchase them, since the products remained available through numerous other online shops. It also pointed out that the blocks were only temporary, and that the plaintiff, by agreeing to the online marketplace's terms and conditions, had accepted the provisions on infringement notifications and thereby waived some of its rights.
What the Court decided
The first instance court's ruling was in favour of the plaintiff. The Court upheld the ruling on all key points.
The Court began by confirming the lower court's finding that the plaintiff's products did not infringe the patents cited in the defendant's notifications. This finding was central to the rest of the decision, since it meant that the notifications were unjustified. If the plaintiff's products were infringing, the defendant, as the user of the platform complaint mechanism, would not be liable for unfair competition irrespective of the other circumstances described below (such as not addressing the plaintiff before filing the complaint through the platform's complaint system).
The Court recognised that an unjustified warning regarding intellectual property rights can constitute an infringement of competition law and interference with an established and operating business. The reasoning behind this is that intellectual property rights holders should not be able to claim broader protection than they are entitled to, and profit from that overreach, without bearing responsibility for the harm this causes to competitors. Within this framework, the Court explained that an obstruction is considered anti-competitive where either the specific aim is to prevent a competitor from developing its business and thereby eliminate it from the market, or the obstruction is such that the competitor can no longer adequately promote its services on the market through its own efforts.
To illustrate how this balance operates in practice, the Court pointed to the established case law on warnings sent directly to a competitor's customers, where the rights holder requires from the customer to stop purchasing or using the allegedly infringing product, threatening legal action if the customer fails to comply. In such cases, the rights holder asserts its allegedly infringed right not against the competitor itself, but against the competitor's customers. The average customer will generally be inclined to comply with any warning without examining its justification in more detail. For this reason, a warning to customers is permissible only if the intellectual property rights holder first issued a warning to the manufacturer but the warning proved unsuccessful, or issuance of a warning to the manufacturer is exceptionally inappropriate under the circumstances.
The Court found that the same reasoning applies to a notification sent to an online marketplace provider. When a platform operator receives a complaint through its complaint system, the platform is in the position in which the average customer is when he or she receives a warning: the operator will understand that the goods or services offered on the platform are possibly infringing and will be inclined to block the listing. The upshot of the Court's reasoning is that, before activating the platform's complaint mechanism, the defendant should have addressed the plaintiff with a warning about the alleged patent infringement.
The Court was unpersuaded by the defendant's framing of the notification to the platform operator as merely flagging a "possible" infringement, since this did not change its practical effect or reduce the defendant's responsibility to verify its claims before acting: the platform operator could still reasonably interpret the notification as an attempt to establish awareness of a potential infringement.
Comment
This ruling is a reminder that complaint systems available on online marketplaces are not a shortcut to enforcing intellectual property rights. While such systems give rights holders a fast and low-effort way to flag alleged infringements, the Court made clear that filing a notification is a serious step that must be taken with care. The care is recommended because, if the notification turns out to be unjustified, meaning that no infringement of the IP right actually has occurred, the rightsholder may become liable for the harm caused to the competitor.
The concern that operators of online marketplaces might be induced to remove contents excessively is not unique to German courts. There is, for example, a line of cases in the United Kingdom, dealing with the situation in which a marketplace provider (such as eBay or Amazon) has little incentive to conduct a substantive IP infringement analysis and typically responds to a complaint by removing the listing. In the well-known case of NOCO Company v Shenzhen Carku Technology Co Ltd (19 December 2023), concerning Amazon's removal of Carku's products from the site, the England and Wales Court of Appeal relied on the Intellectual Property (Unjustified Threats) Act 2017 to reach a decision similar to the Higher Regional Court of Düsseldorf.
The German Court was clear that the prudent first step might be to approach the alleged infringer directly, rather than going straight to the platform. Addressing the platform although the allegation about the infringement of intellectual property rights is uncertain or improbable, may return as a boomerang to the rightsholder. The decision is a signal that marketplace complaint systems should not be used as a substitute for engaging with a competitor directly, and that doing so without first carrying out a genuine infringement assessment carries legal risk.