Legal Updates

Intellectual Property – Patent Infringement – Amendments Disallowed

The claimant in the case of LG Phillips Co Ltd v Tatung (UK) Ltd and Others [2006], held a UK patent for mounting a flat panel display device within a two-part housing, which could be incorporated into products such as laptops or free standing computer monitors. The patent was principally directed at LCD displays for laptops. The claimant brought proceedings against three defendants in the patent county court. It was alleged that the defendants had infringed the patent through the creation of a closed circuit television monitor. The defendants denied infringement, and actually counterclaimed for the revocation of the patent in question on the grounds of anticipation, obviousness and insufficiency.

The claimant then sought to have one of the patent claims amended in order to meet part of the defendant’s case for revocation. The claimant argued that their action would fail if the courts did not allow the proposed amendments. However, the defendants submitted that by allowing the amendments to take place, additional matter would be added to the patent contrary to s.76 of the Patents Act 1977 (“the Act”).

The first proposed amendment meant the removal of the affixation of the module to the front housing. In the original patent, there was no mention on how the module would be attached. The claimant submitted that by making this amendment no additional matter would be added to the patent because in at least one incarnation of the invention, the notion that “the module should not be affixed to the front housing” had been disclosed in the product specification.

The second proposed amendment meant that the fastenings would be behind the flat panel display. This feature appeared in a drawing of one of the preferred embodiments of the invention, but was otherwise unidentified. In the original patent, no mention of this feature having inventive significance had been made.

The judge held that the amendments should not be allowed as they constituted additional matter contrary to s.76. He therefore dismissed the claim for infringement and allowed the case for revocation on the ground that the claimant had conceded that if the amendments were not made, their action would fail. The claimants then appealed to the court of appeal.

Their appeal was dismissed for the following reasons:

§        If the specification disclosed distinct sub-classes of the overall inventive concept, then it should be possible to amend down to one of those sub-classes.   However, in this case the amendments which were sought were only disclosed in a specific context and were not disclosed as having any inventive significance. Introducing them into a claim would have deprived them of that context, meaning that the amendments were not suitable to be added to the claim. This is a process called ‘intermediate generalisation’. This is evidenced more specifically in the second amendment the claimant applied for. The second amendment tried to add an otherwise unidentified feature which had only been shown in a drawing. There was no suggestion that the feature had any inventive significance, and the amendment did not wish to attach any other features displayed in that drawing. This is an excellent example of intermediate generalisation, which is not permitted.

§        It was held that the Act was seeking to prevent the owner of a patent from amending a claim to such an extent that they were effectively seeking to protect a different invention to the one in the original application. Therefore, provided the invention in the amended claim was disclosed in the original application when read as a whole, it would not offend s.76 of the Act. Where the amendment included a disclaimer which narrowed the claim, it was held that a specific disclaimer did not ‘add matter’ if it was inserted into a claim to avoid an 'accidental' anticipation, but it did ‘add matter’ if it was inserted to avoid a 'non-accidental' anticipation. An ‘accidental’ anticipation is one in which a disclosure relating to a remote technological field is made. It can also arise where the subject matter concerned does not help to solve the problem addressed by the patent in question. In the case in question, the first amendment either sought to add a feature to the patent which was not addressed specifically anywhere before, or it sought to add a disclaimer for products which had all the features of the claim save that the module was fixed to the front housing. If the first analysis was correct, then the amendment would be deemed to add new inventive significance to the patent and would offend the rule on adding matter. If the second analysis was correct, then the amendment was effectively a disclaimer included for the purpose of preventing the claim from extending to an item of prior art. It would be difficult to establish that the prior art was in a remote technological field.

The judge was therefore right to have disallowed both amendments.

If you require further information contact us at  Visit or

© RT COOPERS, 2007. This Briefing Note does not provide a comprehensive or complete statement of the law relating to the issues discussed nor does it constitute legal advice. It is intended only to highlight general issues. Specialist legal advice should always be sought in relation to particular circumstances.




Search Shadow


newsletter Shadow


Testimonial Bottom Shadow

testimonial Shadow Middle

More Testimonials

Testimonial Bottom Shadow