In a first-of-its-kind ruling, the IP High Court of Korea has held that a foreign company that advertises and sells products on a foreign e-commerce platform or through a website hosted on overseas servers can infringe a Korean patent, where the online activity is directed at consumers in Korea (Intellectual Property High Court, Decision No. 2023Na10693, May 22, 2025). The decision recognizes that posting an allegedly infringing product on an overseas online platform can constitute an “offer for assignment” (also known as an “offer for sale”) under the Korean Patent Act, bringing such conduct within the reach of Korean patent law even absent proven domestic sales. The parties did not appeal to the Supreme Court and the court decision became final and conclusive on June 10, 2025. 

Background

Under the Korean Patent Act, an “offer for assignment” is one of the statutorily defined forms of “practice” of a patented invention, and an unauthorized offer for assignment can therefore constitute patent infringement. Patent rights are traditionally understood to be territorially bound, meaning that acts occurring outside Korea generally fall outside the scope of Korean patent protection. The central question in this case was whether conduct carried out abroad—specifically, posting a product for sale on a foreign website or e-commerce platform—could constitute a domestic “offer for assignment” under the Korean Patent Act. 

The Facts

The plaintiff, an Italian corporation, holds Korean-registered patents relating to hosiery (sock) knitting machines. The defendant, a Chinese corporation, manufactured similar machines in China, and advertised and sold them on the Chinese e-commerce platform Alibaba and on its own website hosted on servers located in China. The plaintiff argued that the defendant’s posting of the machines for sale constituted an “offer for assignment” of products falling within the scope of the plaintiff’s patented invention, and sought an injunction against infringement together with damages. 

Notably, the court found that the defendant’s online activity was specifically directed at the Korean market: the listings provided detailed product information in Korean, allowed Korea to be selected as a delivery destination, offered the option of payment in Korean won (KRW), and provided a dedicated inquiry and customer-support channel for Korean consumers. 

International Jurisdiction and Governing Law

Since this case involves an Italian corporation (plaintiff) that sought an injunction against a Chinese corporation (defendant) for infringement of the subject patents registered in Korea, the court first reviewed whether a Korean court has jurisdiction over this case. Applying Article 39 of the Act on Private International Law, the court reasoned that jurisdiction lies with Korean courts where the result of an infringement of a Korea-registered patent is likely to occur in Korea, and found that the dispute and the parties had a substantial nexus to Korea. On governing law, the court applied Korean law pursuant to Article 40 of the Act on Private International Law, under which the protection of intellectual property rights is governed by the law of the place of infringement. 

Whether Posting on a Foreign Platform Is an “Offer for Assignment” in Korea

The court first compared the defendant’s machines element-by-element against the asserted claims and found that the defendant’s machines fell within the scope of the patented invention. The court then turned to whether the defendant had “practiced” the invention in Korea. As to whether the defendant “sold” the defendant’s products in Korea, the court found that import-clearance records alone were insufficient to prove that the defendant’s products had actually been transferred into Korea. Nevertheless, the court held that the act of posting the products for sale online amounted to a domestic “offer for assignment,” reasoning that the conduct went beyond mere worldwide accessibility and instead constituted sales solicitation aimed directly at consumers in Korea. 

In reaching this conclusion, the court emphasized the following indicators that the defendant’s activity targeted the Korean market: 

• Users can access the website (http://www.E.com) and change the language to Korean, and if the Korean language is selected, the site is redirected to http://korean.E.com;
• Product information is provided in Korean; 
• Ability to order and receive delivery in Korea; 
• Payment available in Korean won; and 
• A dedicated inquiry and consultation channel for Korean consumers. 

The Ruling

The court granted the plaintiff’s request for injunctive relief, ordering the defendant to refrain from assigning or leasing the accused products and from making any offer for their assignment or lease (including display for such purposes). The decision reversed the lower court, which had dismissed the infringement claim on the view that the key elements of the offer for sale—the seller, the product, and the price—were located overseas. It is the first case that a Korean court has held that online postings by a foreign company outside Korea can qualify as domestic infringement where the foreign company effectively solicits business from consumers in Korea. 

Significance and Key Takeaways

This decision is significant as the first ruling to clarify that cross-border commerce based on foreign servers or platforms may nonetheless be treated as an “offer for assignment” under the Korean Patent Act where it is accompanied by substantive business activity aimed at the Korean market. In effect, the court elevated the practical impact of the conduct and the boundaries of the market it targets over the formal location of the physical server. The ruling reflects a modernized application of the territoriality principle, adapting Korean patent enforcement to a digital economy in which globally accessible platforms are commonplace. 

For clients, the principal practical implications are as follows:

• Online offers can infringe, even without proven local sales. Listings that target Korean consumers may amount to patent infringement in Korea regardless of where the seller or its servers are located. 
• Market-targeting indicators are decisive. Korean-language pages, Korean won pricing, delivery to Korea, and Korean-language customer support are the type of factors courts will weigh in assessing whether conduct is an “offer for assignment” aimed at Korea. 
• Patent holders gain a stronger enforcement tool. Rights holders can act against infringing products marketed into Korea via international platforms even where the seller is based abroad and direct sales are difficult to prove. Regarding litigation strategy, it will be important to specifically establish intentional business activity directed at the Korean market, rather than mere passive exposure of product information. 
• Foreign sellers are on notice. Manufacturers and sellers using online platforms such as Alibaba, or operating multilingual websites, should assess Korean patent exposure where their listings are oriented toward Korean consumers.