The “Sleeping” Trademark Trap
Many business owners believe that once they hold a trademark registration certificate, their rights are secure forever. However, in Korea (as in many jurisdictions), rights come with responsibilities. The most significant of these is the “Duty to Use.”
If a trademark has not been used for three consecutive years, any third party can file a “Non-Use Cancellation Trial.” If the owner cannot prove legitimate use within the relevant timeframe, the registration is cancelled.
Defending these rights requires more than a vague claim of “I’m still in business.” It requires cold, hard, objective evidence. Here are two success stories where Sarang IP turned strict evidentiary requirements into a winning defense.
Case 1: The Product Defense – “Dates are Everything”
Client: CEO Yoon, Audio Equipment Manufacturer (Speakers)
The Crisis: CEO Yoon had been running his speaker company for years when he was hit with a cancellation trial. A competitor claimed his trademark had been dormant for three years. CEO Yoon was baffled—he had been selling speakers the whole time!
The Challenge: In a non-use trial, the burden of proof is on the trademark owner. It is not enough to say, “I used it.” You must prove “When” and “How.” The critical window is the three years immediately preceding the trial filing date.
The Strategy: Building a Timeline Sarang IP moved beyond simple assertions and constructed a forensic timeline of commerce.
- Digital Footprints: We captured screenshots of product pages from his website and e-commerce platforms. Crucially, we ensured the dates of the captures and the timestamps of the listings were visible.
- Customer Voices: We submitted dated reviews from Coupang and blogs. A customer review from 2 years ago praising the “Brand X Speaker” is powerful third-party proof of use.
- The Second-Hand Market: We even utilized transaction records from “Joonggonara” (Korea’s eBay) to show the brand’s circulation in the secondary market.
- The Gold Standard: Finally, we submitted tax invoices and delivery notes. These official documents linked the trademark name directly to specific dates and financial transactions.
Product catalogs used as evidence in a Korean trademark non-use cancellation defense 
Secondary-market resale listings showing the speaker brand in active commercial use 
Dated tax invoices and delivery notes linking the trademark to transactions within the 3-year window
The Result: By providing an unbroken chain of evidence proving use within the 3-year window, we successfully defended CEO Yoon’s rights. The cancellation request was dismissed.
Case 2: The Service Defense – “Follow the Money”
Client: CEO Jo, Advertising Agency
The Crisis: Defending a service mark (like an agency, consultancy, or restaurant) is often harder than defending a product mark. You cannot put a “service” in a box and take a picture of it. CEO Jo faced a cancellation trial and felt helpless, asking, “I did the consulting work myself, but how do I prove it?”
The Challenge: The court doesn’t accept verbal testimony alone. We needed to make the intangible service “tangible” through documentation.
The Strategy: The Paper Trail We explained to CEO Jo that in the eyes of the law, a service exists when money changes hands for it. We focused on the financial workflow:
- The Proposal: We gathered price estimates and contracts sent to clients, all clearly bearing the trademarked agency name.
- The Transaction: We matched these contracts with Deposit Confirmations and bank transfer records. This proved the deal wasn’t just hypothetical—it was executed.
- The Completion: We secured “Certificates of Service Completion” from CEO Jo’s clients, confirming that the work branded under the trademark was delivered.
Certificates of Service Completion obtained from clients as proof of trademark use for services 
Client-signed service completion records proving the branded service was delivered 
Evidence proving the service mark was actively traded in the Korean market
The Result: We proved that the “service” was actively being traded in the market. The specific link between the trademark, the service provided, and the payment received was established. CEO Jo’s trademark remained valid and secure.
Conclusion: Evidence Over Emotion
In a Non-Use Cancellation Trial, the judge does not care about your passion or your future plans. They care about commercial evidence.
- For Products: Keep your invoices, website logs, and packaging proofs organized by date.
- For Services: Ensure your trademark appears on contracts, invoices, and payment receipts.
If you are facing a challenge to your trademark, do not panic. The evidence often exists; you just need a partner who knows how to curate and present it legally.
