LG Philips LCD Co Ltd v Tatung (UK) Ltd & Ors

A patent claim must be as clear as its subject matter reasonably permits. It is construed in the context of the specification and the inventive concept.

An amendment adds matter where it extracts an otherwise unidentified feature from a particular embodiment and inserts it into a claim without its disclosed context. A disclaimer based on undisclosed matter is permissible to avoid accidental anticipation only where the prior disclosure is wholly unrelated and remote.

An appellate court should not disturb a first-instance finding of obviousness unless the tribunal erred in principle, misunderstood or overlooked essential facts or expert evidence, or reached a conclusion unavailable to a reasonable tribunal.

The proprietor of a patent for mounting flat-panel displays sued three companies for infringement. The defendants denied infringement and counterclaimed for revocation on grounds including anticipation, obviousness and insufficiency. The proprietor applied to amend the patent to meet part of the revocation case.

His Honour Judge Fysh QC, sitting in the Patents County Court, refused the amendments as adding matter and found one amendment insufficiently clear. The proprietor had conceded that its action failed if amendment was refused. The judge nevertheless held, on the assumption that amendment was permitted, that there was no infringement and that the claimed invention was obvious. He dismissed the infringement claim and ordered revocation.

The proprietor appealed against the refusal of amendment, non-infringement and obviousness. The central issues were the clarity and permissibility of the amendments, the contextual construction of the amended claim, and the proper appellate approach to obviousness.

1. Appeal dismissed. Neuberger LJ, with whom Leveson LJ and Lord Phillips of Worth Matravers LCJ agreed, held that both proposed amendments constituted added matter under section 76 of the Patents Act 1977. The refusal of amendment was sufficient to dispose of the appeal because the proprietor had conceded that the patent was invalid and its infringement action failed if amendment was refused.
2. A patent claim need not eliminate every possible uncertainty. It must be as clear as its subject matter reasonably admits. The proposed requirement that a fastening be behind the flat-panel display was sufficiently clear. In context, the display meant the whole glass layer, and a fastening wholly or partly behind that glass satisfied the wording. The judge's contrary conclusion under section 14(5) was wrong.
3. The second amendment nevertheless added matter. The specification did not teach that the fastenings must be behind the glass rather than elsewhere behind the display module. Extracting that unremarked feature from certain drawings of preferred embodiments, while omitting the embodiments' other features and assigning the feature inventive significance, was an impermissible intermediate generalisation.
4. The first amendment, requiring that the module not be fixed to the front housing, also added matter. At most, the specification disclosed that arrangement in prior art and possibly in one embodiment. It did not disclose the arrangement as a general or inventive requirement. If treated instead as a disclaimer introduced to avoid prior art, it remained impermissible because that prior art was not an accidental anticipation from a wholly remote or unrelated technological field.
5. On the assumed amended claim, there was no infringement. Construed in the context of the invention's purpose of saving side space, the claim required rear fastenings to be the sole fastening method. A product which also used side fastenings therefore fell outside the claim. The word “frame”, however, was broad enough to include a basic rigid supporting structure rather than only a complete surrounding structure.
6. The finding of obviousness was upheld. An appellate court may intervene only for an error of principle, a misunderstanding or omission of essential facts or expert evidence, or a conclusion unavailable to a reasonable tribunal. The judge had considered the skilled person's mindset and had not employed an impermissible hindsight reconstruction. Expert evidence supported the conclusion that the differences from the prior art involved no inventive step.

1. Court of Appeal (Civil Division): The appeal was dismissed by [2006] EWCA Civ 1774. The refusal of both amendments for added matter, the finding of non-infringement and the finding of obviousness were upheld. The finding that the second amendment lacked clarity was reversed.
2. Patents County Court: His Honour Judge Fysh QC refused the proposed amendments, dismissed the infringement claim and allowed the counterclaim for revocation. No citation for that judgment is stated.