In the matter between African Explosives Limited and Sasol Dyno Nobel (Proprietary) Limited the Commissioner of Patents was tasked to adjudicate whether two amendments of the claims of Sasol's patent should be allowed, or set aside. The patent in question is South African patent number 1991/2194, entitled "Low-energy blasting initiation system and surface connection thereof", granted on 29 January 1992. The Registrar of Patents granted the first amendment on 14 August 1992 and the second amendment on 25 May 2004.

In bringing the application, African Explosives contended that the first amendment should be set aside because it fell foul of section 51(7) of the Patents Act no 57 of 1978 ("the Act"). Section 51(7) stipulates that "No amendment of a complete specification ... shall be allowed if the specification as amended would include any claim not wholly within the scope of a claim included in the specification before amendment". It was argued that the substitution of the words "surface connection" with "surface connection block" served to broaden the scope of the first claim, thereby contravening the provisions of section 51(7). African Explosives stated that "connection" means the stated of being connected, and a claim directed to a "block" is restricted to a block and did not extend to components which are connected to the block, or which were connected to one another by means of the block.

On behalf of Sasol it was argued that the word "connection" has two meanings, firstly, "being connected", and secondly, "a connecting part". On a proper reading of the specification, as originally filed, the word "connection" has the aforementioned second meaning of "a connecting part". A "connection" included, but is wider in scope than a "connector block" and as a result after the amendment claim 1 was fully within the scope of claim 1 of the specification as originally filed, albeit narrower in scope.

The court held that on an ordinary grammatical reading, the word "connection" meant a connecting part because, if read in context, it comprised or consisted of certain features. These features are particular to an object and not to "a state of connection". The connection was a connecting part which is narrower than a connector block. The court accordingly held that the specification, as amended, thus did not include any claim not wholly within the scope of a claim included in the specification before amendment.

In respect of the second amendment, African Explosives contested that the amendment was made in conflict with the provisions of section 51(6) of the Act which reads "No amendment of a complete specification ... shall be allowed if (a) the effect of the amendment would be to introduce new matter or matter not in substance disclosed in the specification before the amendment; or (b) the specification as amended would include any claim not fairly based on matter disclosed in the specification before amendment".

It was contended by African Explosives that, after amendment, some components of the invention were, in the claims, attributed specific features and lay-outs which were not disclosed in the specification before amendment. Therefore, as far as those claims were concerned, the specification included new matter and was not fairly based on matter before amendment. In its answer, Sasol denied the allegations raised by African Explosives, and relied particularly on the figures of the specification in advancing its case.

In coming to a decision, the court referred to the case of Bateman Equipment Limited and Another v Wren Group (Pty) Limited wherein the Supreme Court of Appeal set out the test to be applied when considering whether an amendment offended against section 51(6) of the Act. Firstly, it should be determined whether the objectionable integer has been broadly described in the original specification; then consider whether there is anything in the original specification inconsistent with the integer; and last whether the original specification is wholly silent on the integer. The court satisfied itself with regards test put forth above and held that both amendments were allowable. The court accordingly dismissed the application with costs.

The judgment is interesting in that it shows that in a patent litigation matter the result often depends on the interpretation a court gives to a single word. Every word in a claim should be chosen carefully as it could potentially take centre stage in a patent litigation matter.

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