Regulated by Article 45 of the 2020 Revised China Patent Law and CNIPA Invalidation
Examination Guidelines, utility model patents face high invalidation risks in infringement
lawsuits, a major hidden pitfall for overseas hardware, home appliance and auto component
manufacturers. Unlike invention patents with full substantive examination, utility models
only receive preliminary novelty checks upon grant, leading to a high invalidation rate of
over 45% in official statistics. Many foreign enterprises lose all domestic litigation compensation
due to incomplete prior art evidence and uncertified overseas reference materials during
invalidation proceedings. This case analyzes a German auto parts maker’s full utility model
invalidation loss, clarifies PRB trial standards, and delivers cross-border evidence compliance
guidance.
A German auto radiator manufacturer obtained a Chinese utility model patent for a new heat
dissipation structure in 2022. When filing infringement litigation against three domestic
manufacturers in 2025, the defendants jointly submitted an invalidation request to the Patent
Reexamination Board (PRB), attaching untranslated foreign industrial manuals and overseas
patent publications as prior art. The German patentee made two fatal procedural mistakes: First,
all overseas prior art documents lacked embassy consular authentication and certified Simplified
Chinese translations, which the PRB ruled as completely inadmissible evidence. Second, the
applicant failed to submit comparative test data proving the utility model’s practical structural
advantages over cited prior art, unable to rebut obviousness grounds. The PRB issued a full
invalidation decision. The German enterprise lost all infringement compensation claims, spent
over 130,000 RMB on litigation and supplementary re-filing costs, and abandoned its domestic
component supply market layout.
Utility models bear low examination threshold yet high invalidation risk (Official CNIPA
statistical data). Utility models skip full inventive step substantive examination at grant; only
novelty and practical applicability are preliminarily reviewed. During invalidation trials, the PRB
adopts the same strict three-part obviousness test as invention patents, resulting in a far higher
full invalidation ratio than invention patents. Overseas enterprises often overlook this gap and rely
solely on granted utility models to launch infringement lawsuits.
Mandatory authentication and translation for all foreign prior art. Any overseas patent, product
catalog, foreign journal or industrial manual submitted as prior art must complete Chinese embassy
consular legalization plus standardized Simplified Chinese notarized translation. Unprocessed
foreign materials are directly excluded without probative value during oral hearings.
One-month fixed fee payment deadline for invalidation requests. Petitioners must pay a 1,500 RMB
utility model invalidation fee within 30 days after submitting the request; overdue payment leads to
automatic withdrawal of the case with no extension available.
Three-tier appeal remedy after PRB invalidation rulings. Parties dissatisfied with invalidation decisions
may file administrative litigation with the Beijing Intellectual Property Court within 3 months of
receiving the notice; a further second-instance appeal can be submitted to the Supreme People’s
Court IP Tribunal if the first-instance judgment is unfavorable. All appeal documents still need a
CNIPA-licensed domestic patent agent for foreign holders.
Complete evidence package requirements for utility model defense. To sustain validity in invalidation,
patentees must provide structural comparison drawings, performance test reports and production
practice records to demonstrate non-obvious structural improvements against cited prior art. Mere
verbal arguments without objective test data cannot support the utility model’s stability.
● Conduct comprehensive global prior art retrieval before filing Chinese utility models, and archive
authenticated Chinese translations of all overseas reference documents for potential invalidation
defense.
● Entrust CNIPA-qualified local patent attorneys to pre-audit utility model claims and strengthen
structural distinguishing features to lower invalidation risks.
● Collect standardized domestic performance test data and mass production records of patented
products as core defense evidence once the utility model is granted.
● Track the one-month invalid fee deadline closely if filing counter-invalidation against competitors’
utility models.
● Immediately engage local IP litigators and prepare consular-certified foreign reference translations
once receiving PRB invalid notices.
The utility model system offers fast, low-cost structural protection for overseas manufacturers, yet
the post-grant full obviousness review rule in invalidation proceedings creates irreversible
litigation losses for enterprises with insufficient evidence preparation. This auto radiator invalidation
case fully proves unauthenticated overseas prior art and missing technical comparison data lead to
complete patent nullification. For foreign component and consumer electronics brands entering China,
pre-filing full prior art searches, standardized foreign document notarization and long-term
preservation of product test evidence are essential to stabilize utility model validity during cross-border
infringement disputes.
Hyperlink List：
● CNIPA English Official Guide to Patent Invalidation Procedures:
https://english.cnipa.gov.cn/art/2012/12/13/art_2699_160810.html
● Full English Text of 2020 Revised China Patent Law Article 45:
