Coway(021240) and Kyowon Property are locked in a patent dispute over a water purifier's dispense volume setting and auto-return function. The two companies have been contesting water purifier design and possible patent infringement since 2024, and this is the first time issues tied to the dispense function have been confirmed. Coway, the industry leader in water purifiers, is expanding the scope of intellectual property (IP) protection beyond design similarity to product functions.
According to mid-sized corporations and the legal community on the 27th, the Intellectual Property Trial and Appeal Board recently dismissed Kyowon Property's invalidation trial filed against Coway's patent for an "electronic water dispensing device." Kyowon Property designs and develops products for the Kyowon Wells home appliance brand and offers rental services. The board found Coway's patent was not a function that could be easily implemented by combining existing technologies.
The patent Kyowon Property challenged allows users to select the amount of water dispensed from a purifier in multiple steps and to set the amount they use most often as the default. If a different volume is selected
and used, the function also returns to the preset default after a period of time.
For example, if a user sets one cup as the default, even if the user temporarily dispenses two cups or dispenses consecutively, the purifier will revert to the one-cup setting after a certain time. This reduces the hassle of having to choose the frequently used dispense volume every time water is drawn.
Coway applied for the related patent in Apr. 2012 and registered it in Jan. 2019. Then, in Aug. 2024, determining that Kyowon Property was using a similar function, it filed a lawsuit seeking to ban patent infringement. Kyowon Property filed a trial last Nov. to invalidate the patent. Coway partially amended the patent in Feb. this year.
Kyowon Property argued that Coway's patent could be easily implemented based on technologies applied to existing ice makers and refrigerator water dispensers, so novelty and inventive step should not be recognized. It said overseas ice makers have functions to set the time water flows in multiple steps, and the function of reverting to a default state after a certain time has also been widely used in home appliances.
However, the Intellectual Property Trial and Appeal Board did not accept Kyowon Property's claims and approved Coway's patent amendment. The board determined that existing technologies only set the water flow time to one of 5 seconds, 10 seconds, or 15 seconds, and do not have a separate default value distinct from the set time.
In particular, the board found Coway's patent clearly different in terms of user convenience because, even if a different amount of water is drawn, it returns to the preset default after a period of time, and it would be difficult to implement this easily with prior technologies.
Coway holds about a 40% share of Korea's water purifier market, maintaining the No. 1 position. CUCKOO Homesys(284740), Kyowon Wells and others have entered the water purifier business and rolled out similar designs and functions, prompting Coway to strengthen IP protection through legal procedures.
A legal community source said, "If either side contests the Intellectual Property Trial and Appeal Board's decision, the case moves to the Intellectual Property High Court." The source added, "As the water purifier market grows and the gap in product functions narrows, not only appearance but also detailed operating methods are becoming the subject of disputes," and "even if a patent's validity is maintained, actual infringement and liability for damages are determined in separate lawsuits."