UPC_CFI_337/2025
FINING OF BOROALUMINO SILICATE GLASSES
TCL Europe SAS sought revocation of Corning Incorporated's EP 3 296 274 (fining of boroalumino silicate glasses) before the Central Division Munich on grounds of added matter, lack of novelty, and lack of inventive step over multiple prior art references. The Central Division dismissed all attacks, establishing that selection of a closest prior art example involving hindsight is impermissible and that interdependent claim features must be assessed together in the objective problem, not decomposed; TCL was ordered to bear Corning's legal costs.
No added matter: claim 1 of EP 3 296 274 as granted does not extend beyond the application as filed
RespondentLegal basis: Art. 123(2) EPCNote: The Central Division rejected TCL's added matter attack; specific reasoning not fully reproduced in excerpt but implied by dismissal of all invalidity grounds.
Novelty of claim 1 maintained over all cited prior art documents
RespondentLegal basis: Art. 54 EPCNote: Court found none of the prior art references anticipating claim 1 of the glass composition patent.
Inventive step: selection of a specific example composition as closest prior art starting point involves hindsight where no pointer exists in the disclosure
RespondentLegal basis: Art. 56 EPC; problem-solution approachNote: Court held that absent a specific reason or pointer in the prior art itself, selecting a particular example merely because it comes closest to the claimed subject matter risks hindsight.
Inventive step cannot be assessed by decomposing interdependent claim features into separate sub-problems
RespondentLegal basis: Art. 56 EPC; problem-solution approachNote: Court ruled that ignoring interdependencies among claim features and dividing the objective problem into separate problems amounts to hindsight reasoning.
Claim 1 lacks novelty over cited prior art range disclosures
ClaimantLegal basis: Art. 54 EPCReason: Court found the numerical ranges in the prior art did not anticipate the specific claimed composition; disclosure of overlapping ranges alone insufficient.
Claim 1 lacks inventive step starting from D14 (float process glass) combined with D16 (refining agents)
ClaimantLegal basis: Art. 56 EPCReason: D14 relates to float processes and its liquidus viscosity requirements differ from those needed for downdraw; D16 teaches Sb2O3 as refining agent whereas the claim purposively excludes antimony and arsenic, so D14 and D16 do not point the skilled person toward the claimed solution.
Inventive step challenged by reference to Chinese Supreme People's Court judgment on a related Chinese patent
ClaimantLegal basis: Art. 56 EPCReason: The Chinese judgment concerned a different patent with different claims and applied a Chinese law inventive step test that differs from the UPC approach; not relevant to the outcome.
Experimental report D41 relevant to patentability of auxiliary requests
ClaimantReason: Because all attacks on the patent as granted failed, the condition for auxiliary requests was not fulfilled and D41's admissibility need not be decided.
Browse other cases on this principle.
- D14Obviousness combination
- D16Obviousness combination
- D19Obviousness combination
- D40 (expert opinion)Background
- D41 (experimental report)Background
- D42-D45 (Chinese court judgment)Background
The patent concerns a boroalumino silicate glass composition with defined ranges (including purposive exclusion of antimony and arsenic as refining agents) suitable for downdraw glass manufacturing. The Court emphasised the interdependency among features such as liquidus viscosity and the antimony/arsenic exclusion as jointly solving the objective problem, and rejected decomposition of these features into separate sub-problems.