Case No. IP-2018-000199

40.Temporary fasteners were part of the common general knowledge. An example of their use is given in the second paragraph of the Patent specification and was recognised by both experts. This is the fixing of a “skin panel” of an aircraft wing to the skeleton of the wing. The panel is held in the correct position relative to the skeleton by temporary fasteners. Permanent fasteners are then installed, after which the temporary fasteners are removed. 41.Both experts distinguished “fly-away” fasteners, which remain in place even when the aircraft enters use and “non-fly-away” fasteners which are removed before flight, generally shortly after they are no longer needed. 42.The claim does not characterise the fastener as being temporary, but “removable”. As a matter of ordinary English the two words do not mean the same thing. 43.Neither expert said that “removable” was a term of art. No doubt any fastener can be removed with the application of sufficient force but neither expert understood “removable” as used in the Patent to be meaningless on the ground that all fasteners are removable in that sense. Nor do I. 44.Mr McKay took the meaning of “removable” from the specification. He understood it to mean a temporary fastener of the type referred to in the second paragraph, which is entirely removed after it has completed its task of temporary fastening. A removable fastener is a non-fly-away fastener. That was Kwikbolt’s contention at trial. 45.Mr Jack countered this by saying in his report that the skilled person would have known of the E-Nut fasteners and that these were both fly-away and removable, implying that the skilled person would contemplate the possibility that fasteners could be both. But as I have said, in cross-examination he conceded that it would be reasonable to suppose that the E-Nut was not well known by 2008. Also, Mr McKay was not challenged on his evidence that the E-Nut is not removable because its sleeve insert remains secured to the workpiece. 46.Kwikbolt’s contention that a “removable” fastener is a non-fly-away fastener introduces an impermissible temporal element into claim 1. It is a product claim. To fall within the claim a fastener must satisfy the claim structurally, be suitable for use as a blind fastener and be suitable for removal. There is no requirement that the fastener must be removed before flight or at any other particular time. In principle, a fastener could be both fly-away and removable – if it were only ever removed during aircraft maintenance for instance. 47.Mr Jack spoke of what he called “key characteristics” of a removable fastener, namely the provision of dowelling support and not being of a nature to create foreign object damage. Mr McKay said that a removable fastener will not necessarily provide dowelling support and was not challenged about this. 48.A removable fastener may have this or that undesirable characteristic, but the presence of any of these does not perforce mean that it is not a removable fastener. Moreover, cross-examination of Mr Jack on this point oscillated between use of the terms “temporary” and “removable” without establishing whether a temporary fastener as understood at the priority date was the same thing as a removable fastener of the Patent. 49.There must be a sliding scale of difficulty in removing a fastener, with a point beyond which a skilled person would cease to regard it as removable. Neither expert addressed the meaning of “removeable” in exactly that way, nor was it put to either of them in that way. If there was a commonly held criterion by which the skilled person would have understood whether a fastener is removable, it did not emerge from the experts. 50.Airbus’s contention was that a fastener is removable if it can be removed without destroying the fastener. Mr Jack said in cross-examination that an essential requirement of a removable fastener was that it did not cause damage to the workpieces being clamped. 51.This contention and evidence provided the best approach to the meaning of “removable” that was available. I conclude that a fastener is removable within the meaning of the Patent if it is suitable for removal in its entirety from the workpieces which it is clamping without thereby causing significant damage either to the fastener or to the workpieces.