Dyson cleans up again

The IPKat has been reading yet another monster judgment from the Patents Court, Dyson Technology Ltd v Samsung Gwangju Electronics Co Ltd [2009] EWHC 55 (Pat), which issued just a couple of days ago on 22 January.  Alexa Highfield of Wragge & Co., the instructing firm for the claimant, was kind enough to let the IPKat peruse a copy of the judgment before it made its appearance online here.  Wragge & Co.'s particular take on the case can be read here. 

Dyson applied for revocation of two of Samsung's UK patents,  GB2424603 and GB2424606, both of which had been filed in 2005 and granted in 2007. Both patents related to cyclonic vacuum cleaners, or "cyclonic dust separating apparatus" as the patents called them.  Dyson claimed that the patents were invalid over various cited documents, and over their own vacuum cleaner models DC07 and DC08, both of which were based on their "Root Cyclone" technology, developed before the priority date of the patents.  Intriguingly, one of the documents cited by Dyson to attack Samgsung's patents was a Japanese utility model from 1977 (pictured right), showing a multicyclone vacuum cleaner that predated even Dyson's earliest patents on bagless vacuum cleaners.  The IPKat wonders whether, if this was brought up at the time the Dyson v Hoover case was being heard back in 2000 and 2001, this might have affected the outcome.  As we all know, Dyson prevailed that time and their patent was upheld. 

Samsung largely failed to show that there was much that was valid in their patents over the art known in 2005.  They seemed to realise this, and filed requests for amendments under section 75 to both of their patents, which involved a substantial re-writing of the claims.  Arnold J went to great lengths to determine whether Samsung's amendments complied with the requirements of section 76(3)(a), which prevents amendments being made that result in the specification disclosing additional matter.  Most of the amendments fell foul of this, and were disallowed, but a couple of their amendments were both allowable and not invalid for lack of novelty or inventive step.  The end result, as far as the IPKat can work out, is that at least one of the claims (in the '606 patent) would stand as being valid after all this.  

The IPKat cannot fault Arnold J's expert and very thorough job of going step by step through each of the issues involved, and is very impressed by the extensive citation of pretty much all the relevant case law on each subject along the way.  Although the judgment overall does not seem to be groundbreaking in any way, it seems to be a very good case study in how to go about looking at validity of patents and all that entails.  

What is puzzling the IPKat, however, is the absence of any arguments or discussion on the other bit of section 76(3), part (b), which states that no amendment to a patent shall be allowed if it "extends the protection conferred by the patent".  This issue, which is often looked at in detail in EPO opposition proceedings under the equivalent provision of Article 123(3) EPC, is designed to prevent the patentee from broadening the scope of their claims in any way after grant.  In effect, this means that any amended claims should not bring something within the scope of the patent that was not within its scope as-granted.  Was section 76(3)(b) simply not an issue for Dyson in this case, or was it just missed out? Given the extensive re-writing of the claims by Samsung, the issue should perhaps have been at least looked at.  All the discussion about admissibility of amendments, however, concentrated on whether the amended claims were based on the specification as-filed, and there is apparently nothing about how they affected the scope of the claims as they were granted.  Can any readers shed further light on this?