Interlego A.G. is the patentee under Australian Letters Patent No. 229,550 building blocks" and sues for infringement by the defendant, Toltoys Pty. Ltd., of its monopoly. Toltoys counterclaims for revocation of the first claim contained in Interlego's letters patent upon a number of grounds. (at p462)

2. Each of the parties markets sets of children's building blocks made of plastic, brightly coloured and predominantly of cuboid shape, a feature of which is that the blocks will interlock securely with one another so that simple structures may be built with them. (at p462)

3. The plaintiff's "Lego" blocks are constructed with one or more, usually at least four, solid, circular, flat topped projections ("primary projections") on their top surface, the bottom of the block being open and, in all but the very smallest size block, containing within the cavity of the block one or more projections ("secondary projections") each of which takes the form of a hollow cylinder reaching down to the open bottom of the block and having an open end at its extremity. (at p462)

4. These blocks may be securely interlocked when placed directly one on top of another because the external surface of each secondary projection within the open end of the upper block will clamp between opposing external surfaces of four primary projections on the upper surface of the lower block. When not positioned the one directly over the other but rather so that one projects out over the base of the other, clamping may still be obtained but this may involve only two or, in certain positions, one primary projection being clamped against the external surface of a secondary projection. In such cases the internal surfaces of the walls of the upper block play an essential part in the clamping process and in the case of the first interlocking arrangement described above, when four primary projections are engaged against the external surface of a secondary projection, those walls add a further clamping surface and prevent rotational movement. All these instances of clamping action I shall refer to as cross-sectional clamping, as distinct from a male-female form of clamping. In the case of the very smallest Lego block, which lacks any secondary projection and has but one primary projection, it may be interlocked on top of another block by clamping the open cavity at its bottom over a primary projection, thus interlocking by means of a male-female clamping action ; there also exists a wide, shallow block, rather in the form of a base plate, having multiple primary projections on one side and multiple secondary projections on the other, which because of its shape permits of other blocks of conventional shape being interlocked with it either by a cross-sectional clamping or by means of a male-female clamping action, primary projections on the one being inserted into the interior of the hollow cylinders formed by the secondary projections of the other. Apart from these two instances all other interlocking is effected by cross-sectional clamping. (at p463)

5. The defendant's "Toltoy Brix", said to constitute an infringement, have a number of primary projections on their top surface, the interlocking effect in their case being obtained by the cross-sectional clamping of the primary projections of a lower block between the interior of the sides of the hollow block above it and the sides of a series of partitions within that hollow which run across the block at forty-five degree angles to its longer sides and divide the hollow of the block into a series of small compartments. (at p463)

6. The infringement complained of relates only to claim 1 of Interlego's letters patent; likewise it is only claim 1 that is attacked as invalid in the defendant's counterclaim. Claim 1 reads :

"1. A toy building set comprising a plurality of hollow

blocks open at one face and adapted to be connected together

by means of projections extending from the bottom faces of

said blocks, and wherein some of the blocks are provided with

at least one projection (primary projection) at the bottom face

opposite the open face, and some of the blocks are provided

with at least one projection (secondary projection) arranged

within the cavity of the block, characterised in that the

positions and dimensions of the secondary projections relatively

to the positions and dimensions of the primary projections

are such that, in a pair of assembled blocks the lateral face or

faces of at least one primary projection of one block will be

clamped against the lateral face or faces of at least one

secondary projection of the adjacent block."

7. The complete specification begins by stating that: "This invention generally relates to toy building sets comprising a plurality of building element and, more particularly, to toy building bricks or blocks comprising a hollow body open at one face and adapted to be connected together by means of projections extending from the face of the elements and arranged so as to engage protruding portions of an adjacent element when two such elements are assembled", and goes on to state the principal object of the invention as being to provide improved coupling means for clamping toy building blocks together in any desired relative position ; it refers to male-female locking arrangements as being well known in building blocks but says of them that they fail to solve "the problem of providing improved coupling means for interlocking adjacent blocks in a vast variety of combinations". It then proceeds to offer a solution based upon such an interrelation of the relative dimensions and positions of primary and secondary projections that in a pair of assembled blocks the lateral faces of at least one primary and one secondary projection will be clamped against one another. It is said that the projections need not be cylindrical in shape but, if they are, an equation is given defining the diameter of the secondary projections and of the width of the cavity of the hollow block. (at p464)

8. After describing the various drawings accompanying the specification it is remarked that if secondary projections are tubular it is advantageous that the cavity within the tube be substantially equal to the diameter of primary projections so that the previously known male-female method of assembly may be combined with the principal feature of the invention, namely the previously mentioned arrangement of primary and secondary projections. (at p464)

9. Reference is also made to the part played by the side and end walls of the hollow blocks in the interlocking of blocks but it is pointed out that theoretically it is possible to omit those walls entirely. (at p465)

10. There then follow sixteen monopoly claims, commencing with claim 1 which I have already set out. (at p465)

11. Although in this case argument ranged over a wide area the action can, I consider, be disposed of with only passing reference to a number of the issues which were debated before me. I have concluded that claim 1 of the plaintiff's letters patent is defective and does not entitle the plaintiff to the relief it seeks in this action but should instead be the subject of an order for revocation, as claimed in the defence and counterclaim. (at p465)

12. In explaining the scope of claim 1 counsel for Interlego contended that the claim was limited to toy building sets which included in their component parts several open ended hollow blocks adapted to be connected together by means of projections extending from the bottom faces of the blocks, some of which blocks had one or more primary projections and some of which had one or more secondary projections, so placed and of such size that in assembled blocks, however assembled, the lateral face of at least one primary projection would be clamped against the external lateral face of a secondary projection. (at p465)

13. By limiting the claim to instances where clamping involved only the external lateral face of secondary projections it was sought to exclude from the monopoly claimed the feature of male-female clamping action involving the internal lateral face of secondary projections and which was, on the face of the specification, acknowledged to have been at all times a well known existing mode of assembly of building blocks. (at p465)

14. Counsel for Toltoys, on the contrary, denied that the claim could be so limited ; the claim, he said, referred simply to a lateral face and when a secondary projection was in the form of a hollow cylinder the reference to a lateral face applied equally to the internal as to the external surface of such a cylinder. The consequence was, he said, that the long familiar male-female clamping action was included in the claim which, accordingly, was much too wide, embracing as it did what the specification itself acknowledged to be prior art. (at p465)

15. If full recourse can, in this case, be had to the body of the specification to qualify the meaning of claim 1 the result will no doubt be that it may be inferred that claim 1 makes no claim to monopoly so far as male-female clamping is concerned. The question is whether the body of the specification may be used for this purpose. (at p465)

16. In Welch Perrin & Co. Pty. Ltd. v. Worrel [1961] HCA 91; (1961) 106 CLR 588 both Menzies J. and, on appeal, the Full Court had recourse to the body of the specification for the purpose of interpreting the claims and resolving ambiguities and there is no dearth of authority for such a course - see Blanco White's Patents for Inventions, 3rd ed., p. 51 and Terrell on the Law of Patents 11th ed., (1965), p. 67 and cases there cited - so long as the use made of the body of the specification is to resolve ambiguities or clarify that which is uncertain in meaning. However it is well established that to go further and use it so as to restrict, expand or qualify what appears in the claim is wholly inadmissible - Ingersoll Sergeant Drill Co. v. Consolidated Pneumatic Tool Co. Ltd., per Lord Loreburn (1907) 25 RPC 61, at p 83 . (at p466)

17. The general principle which appears to me to emerge from the authorities is that, although claims must always be read in their context, clear and unambiguous wording in a claim is not to be departed from because of indications culled from the body of the specification. The claim defines the invention - Patents Act 1952-1966, s. 40 (1) (b) ; it is the claim which, as Lord Russell of Killowen said in Electric & Musical Industries Ltd. v. Lissen Ltd. (1938) 4 All ER 221, at p 227 ; 56 RPC 23, at p 41 "alone defines the monopoly ; and the patentee is under a statutory obligation to state in the claims clearly and distinctly what is the invention which he desires to protect." (at p466)

18. As the joint judgment of the Full Court in the Welch Perrin Case emphasized (1961) 106 CLR, at p 610 , what is to be construed is : "a public instrument which must, if it is to be valid, define a monopoly in such a way that it is not reasonably capable of being misunderstood." It was to resolve ambiguity and obscurity that the body of the specification was resorted to in that case, so that, by reading the claim in its context, what was otherwise unclear became clear. Their Honours went on to recall that it had often been insisted that : "It is not legitimate to narrow or expand the boundaries of monopoly as fixed by the words of a claim by adding to those words glosses drawn from other parts of the specification." (1961) 106 CLR, at p 610 . (at p466)

19. In the present case I think that, due to the form which claim 1 takes, counsel for the plaintiff was obliged to resort to the very mode of interpretation which the authorities repudiate as inadmissible. The claim refers to "the lateral face or faces" of a secondary projection, without any limitation to any particular face. It must necessarily be exclusively in reliance upon the body of the specification that the plaintiff seeks to read down those words so as to avoid a construction admittedly too wide, thereby restricting them to the external lateral faces of such secondary projections as are hollow cylinders. (at p466)

20. In Electric & Musical Industries Ltd. v. Lissen Ltd. (1938) 4 All ER 221 ; (1939) 56 RPC 23 , neither Lord Russell, who would have dismissed the appeal, nor Lord Porter, who took an opposite view, had any doubt but that, if claims have a clear meaning in themselves, language in the body of the specification cannot be used to alter that meaning. (at p467)

21. I conclude that the meaning of claim 1 in the presently relevant respect is quite clear ; it says of those blocks in a toy building set which have projections that they are characterized by the respective projections being so positioned and of such dimensions that the lateral face or faces of primaries and secondaries will, in a pair of assembled blocks, be clamped against one another. The claim extends to all those cases in which this clamping of lateral faces occurs. What then is the ordinary meaning of "lateral face"? The Shorter Oxford English Dictionary gives, as the first meaning of "lateral", "of or pertaining to the side" and this is, I think, the sense in which it should be understood in claim 1. One meaning of the noun "face" is "the surface or one of the surfaces of anything" and I think that the phrase "lateral face" means those surfaces of a projection which are situated on its sides. (at p467)

22. It emerged from the evidence that the phrase had no special meaning known to experts in the art. An engineer called on behalf of the plaintiff said that "lateral", when used in relation to the face of an object, meant any side face and that a tubular object had two lateral faces, the inside and the outside lateral face. An engineer called on behalf of the defendant described a projection of tubular character open at both ends as having two lateral faces, one outside and one inside lateral face. (at p467)

23. No doubt the reference in the claim to primary and secondary projections does justify some reference back to the body of the specification for the meaning of these terms which are there defined but such a reference back throws no light upon the meaning of "lateral face" advantageous to the plaintiff. (at p467)

24. It is, of course, only where secondary projections take the form of hollow tubes, cylindrical or otherwise, that the plaintiff feels the need to import a limitation into claim 1 so as to exclude a particular type of lateral face, described as "internal". Thus it insists that the series of thin internal partitions, which run from side to side of the allegedly infringing blocks and whose lateral faces when in contact with the faces of primary projections provide the requisite clamping surfaces, do possess two faces either of which may be used, in conjunction with the faces of other partitions, for the clamping of primary projections, the plaintiff drawing no distinction between them ; an infringement is alleged whichever side is employed. (at p468)

25. The diagrams numbered as figs. 7 and 8 on the drawings accompanying the plaintiff's letters patent contain secondary projections which might be described as squared-off hollow tubes the sides of which have been slit lengthwise so that each resultant segment of the tube forms a distinct secondary projection in itself. By this lengthwise slitting what otherwise would be a continuous internal lateral face has become a series of independent faces, none of them properly to be described as internal. No doubt many variously shaped secondary projections could be devised, some with one continuous lateral face, some with two or more distinct lateral faces and some having lateral faces which might be designated internal ; moreover a lateral face may be all in the one plane, may curve in one dimension only, being in a plane in the other, as in the case of a cylinder, or may curve in all dimensions, as in the case of a sphere. When there may be such a variety of lateral faces there would appear to be little justification for treating the words "lateral face" in the claim as inclusive of all but those which happen to possess the characteristic of being internal, relative to the secondary projection of which they form a part. (at p468)

26. This is not, I think such a case as that of which Luxmoore J. spoke when he said in British Thomson-Houston Co. Ltd. v. Guildford Radio Stores (1937) 55 RPC 71, at p 88 that it is necessary to introduce into every claim limitations dictated by common sense after a perusal of the whole of the specifications. Nothing his Lordship there said appears to me to justify the step of reading down "lateral face" so as to exclude an internal lateral face. (at p468)

27. For the foregoing reasons I conclude that claim 1 claims a monopoly in terms which are wide enough necessarily to include toy building sets in which some blocks may be assembled together by clamping primary projections against the internal lateral face of secondary projections. This is what is referred to earlier in the specification as part of the prior art and at the hearing of this action it was common ground that such a male-female mode of clamping together toy blocks was not novel. It follows, therefore, that the subject matter of the claim extends beyond that which the plaintiff, as patentee, has in fact invented. (at p468)

28. I am conscious of the fact that, in coming to the conclusion I have, I am treating the plaintiff as claiming a monopoly which includes a feature which it has itself described in the body of the specification as prior art. This, however, appears to me to be the necessary consequence of the words of claim 1, just as it was in the case of the words used in the specification considered in Kynoch & Co. Ltd. v. Webb (1899) 17 RPC 100 , where Lord Shand particularly referred to this aspect at p. 110. In Chapman & Cook v. Deltavis Ltd. (1930) 47 RPC 163, at p 175 , Clauson J. referred to the consequence, as he saw it, of a patentee mistakenly claiming a monopoly for a particular form of thing which earlier in the specification had been recited as common knowledge ; he would, he said, have thereby "recited himself out of Court". In Sonotone Corporation v. Multitone Electric Co. Ltd. (1955) 72 RPC 131, at p 140 Evershed M.R., delivering the judgment of the Court, doubted whether anything in the way of an estoppel against the patentee could arise in such circumstances. However, where it is not a matter of an injudicious admission as to prior art but rather the claiming of a monopoly in an area which, it is common ground, is already commonly known and exploited it is clear that such a claim is bad. (at p469)

29. I turn now to a quite distinct ground of attack upon the validity of claim 1. Counsel for the plaintiff said that claim 1 was drawn so as to define the invention for which monopoly is claimed by reference to the effect achieved, there being two elements of that invention, neither itself novel but said to be novel when employed in combination ; the first was the interrelation of primary projections of one block with secondary projections of another block, the second was the use of the inherent elasticity of the constituent material of which the blocks are made. The proper combination of these two features is claimed to result in a clamping action and it is this which provides the plaintiff's improved means of connecting toy building blocks. It was said that the internal walls of the blocks need play no part in this clamping action and certainly claim 1 makes no reference to any role which they are called upon to play ; it is only the projections which the claim treats as the clamping device. (at p469)

30. Once this is appreciated it becomes apparent that there is a curiosity involved in claim 1 ; the action of clamping, as instanced by the example of the common vice, necessarily involves four surfaces, the two sides of the object to be clamped and two surfaces against which those sides may clamp. Claim 1 however refers only to blocks having at least one primary projection and at least one secondary projection, the respective lateral faces of these projections being clamped ; it does not explain how this clamping effect is to be produced. No doubt it is to the body of the specification that resort is to be had for directions concerning the achieving of the clamping effect but it is the claim itself that must describe the area of monopoly claimed ; in the absence of any definition of the other two surfaces employed to produce the clamping effect the monopoly claimed must extend to all cases in which clamping takes place between the side of one projection and the side of another, regardless of how those projections are sustained in their positions relative to one another so that the restraint necessary for the clamping action is produced and maintained. (at p470)

31. The terms of claim 1 may be contrasted, in this respect, with certain subsequent claims, of which claim 2 provides a convenient example. In claim 2 projections are said to be cylindrical in shape, the secondary projections being arranged in the median plane of the open face of the block, their diameter within the cavity of the block being determined by the equation earlier referred to, which is set out both in claim 2 and in the body of the specification. Because the secondary projections are stated to project down as far as the median plane of the block's open face and because this equation uses as two known factors the width of the cavity of the block and the diameter of the primary projection, the nature of the clamping mechanism is revealed ; two additional surfaces are identified, the inner wall of the block containing the secondary projection and the side of the primary projection which, because of the terms of the equation, will come into close contact with it. The necessary restraint is then exerted because the secondary projection is integral with the block, against the inner wall of which one face of the primary projection will press. (at p470)

32. Accordingly in claim 2 the clamping mechanism is fully described and the area of monopoly is restricted to instances in which clamping of projections against one another occurs and is maintained because of the relationship between the space existing between the secondary projection and the inner wall of one block and the diameter of the primary projection of another block. In claim 1, however, no hint is given of how the surface of one projection is to be clamped and maintained in a clamped state against the surface of another. (at p470)

33. The consequence is that claim 1 lays claim to a monopoly in every instance in which, in blocks with one or more primary or secondary projections, clamping occurs between a surface of one projection and a surface of another ; all that is required is that assembly of the blocks should produce clamping due to "the positions and dimensions" of one projection relative to those of the other. The reference to relative "positions" adds nothing other than that the two projections must abut, which is self evident because they are said to be clamped together ; likewise reference to the relative "dimensions" of the projections adds nothing by way of any limitation to the claim. (at p471)

34. If, as was said by counsel for the plaintiff, it is the combination of two features, interrelation of projections and elasticity of materials, that is the invention, the absence of any description of what interrelation is in question leads to great width of claim. No doubt, as was exemplified in No-Fume Ltd. v. Frank Pitchford & Co. Ltd. (1935) 52 RPC 231 , a claim may validly be limited merely by the result to be attained but, as is said in Terrell on the Law of Patents, 11th ed., (1965), p. 96, this may only be done if "the limitation is 'sufficient to characterise the construction of the article claimed' Mullard Radio Valve Co. Ltd. v. British Belmont Radio Ltd. (1938) 56 RPC 1, at p 16 ." Here the limitation, by reference to the result, the attaining of a clamping effect between two projections, does not characterize the construction of the toy building blocks. (at p471)

35. In Raleigh Cycle Co. Ltd. v. H. Miller & Co. Ltd. (1946) 63 RPC 113 Vaisey J., at first instance, gathered together a number of passages from the cases defining the function of a claim and certain of these, culled from the judgment of Lord Russell of Killowen in Electric & Musical Industries Ltd. v. Lissen Ltd. (1938) 4 All ER 221 ; 56 RPC 23 , Lord Normand described, on appeal (1948) 1 All ER 308, at p 319 as an authoritative exposition of the function of the claim in a specification. It suffices, for my purpose, to refer specifically to one of these passages, in which it is said (1938) 4 All ER, at p 224 ; 56 RPC, at p 39 :

"The function of the claims is to define clearly and with

precision the monopoly claimed, so that others may know the

exact boundaries of the area within which they will be

trespassers."

In the present case claim 1 fails in this respect, it nowhere defines with clarity or precision, or indeed at all, the exact boundaries of the area over which monopoly is claimed. On the contrary the matter is left quite indefinite. (at p471)

36. There is here no "rule ascertained and defined by the patentee" which those who wish to manufacture toy building blocks may follow, by making no more than simple experiments, in order to achieve the result claimed in claim 1 - Lord Hanworth M.R. in the No-Fume Case (1935) 52 RPC, at p 240 citing the words of Lord Hatherley in British Dynamite Co. v. Krebs (1896) 13 RPC 190 . No doubt the patentee is not required to limit the area of monopoly by reference to specific measurements or specific shapes, but he must, I think, condescend to more detail than is provided in claim 1 and must, as Lord Hanworth says (1935) 52 RPC, at p 241 , provide a sufficient indication of what is the area which the patentee asks for as his monopoly. To put the matter another way and employing the language of Romer L.J. in that case (1935) 52 RPC, at p 244 , it suffices if the various integers composing the invention are described, together with their manner of arrangement and relative proportions, so that all that remains to be done is to discover within what limits those proportions should lie. But in this claim some relevant integers are omitted and no indication whatever is given as to manner of arrangement. (at p472)

37. It follows that this claim does not comply with s. 40 of the Act in that it does not define the invention and is not clear. It was said that the omission of all reference to the walls of a block operated to make inutility, within s. 100 (1) (h) of the Act, an available ground of invalidity. This was so because the claim could not be shown to produce any useful result in the form of the assembly of blocks by the clamping together of projections. This does not, however, appear to me to be a proper conclusion ; as claimed the invention is necessarily useful since it is claimed in terms of the result said to be achieved. It is, rather, the lack of definition of the invention and not its inutility that appears to me to be a vice of claim 1. (at p472)

38. The effect of the two distinct criticisms made of claim 1 which I have discussed and held to be well founded is that the claim is invalid as alleged in par. 6 of the defence and in par. 5 of the counterclaim and should be revoked. This invalidity may be described as grounded both upon want of subject matter, alleged in par. 6 of the particulars of objection, and upon non-compliance with the requirements of s. 40 of the Patents Act 1952-1966, as alleged in par. 2, that non-compliance arising because the claim lacks clear definition of the invention, involves ambiguity and is not fairly based on the matter described in the specification. (at p472)

39. A variety of other attacks was made by the defendant upon the validity of claim 1, its defence being, in effect, limited to the question of validity since the fact of infringement was not really in issue when counsel came to address me. Since these were argued in some detail I propose to deal shortly with three of these further defences. (at p472)

40. It was contended on behalf of the defendant that the plaintiff's invention was anticipated by French letters patent No. 1,141,279 which were first open for inspection in the Canberra Patent Office library on 6th February 1958. However, the plaintiff claims a priority date of 28th January 1958 for claim 1, despite the fact that its application was not lodged until 12th January 1959, and does so because its application was a convention application to which Pt XVI of the Act applies, claim 1 being said to be "fairly based on matter disclosed in" a Danish patent application of 28th January 1958 and thus gaining priority according to the date of that disclosure. (at p473)

41. Two questions are involved ; can claim 1 of the letters patent in suit take advantage of the Danish priority date, if so no question of possible anticipation by the later French letters patent will arise. If not, the second question would arise, whether the French letters patent do in fact anticipate the letters patent in suit. I have found it unnecessary to consider this second question since I have concluded, favourably to the plaintiff, that claim 1 is entitled to the earlier priority date of 28th January 1958. (at p473)

42. If a convention application claim is to have a priority date earlier than the date of application what Pt XVI of the Act requires, so far as presently relevant, is that the claim be fairly based on matter claimed or disclosed in the overseas basic application - s. 145 (a). Prior disclosure of the subject-matter, without necessarily its incorporation in the claims of the basic application, suffices so long as there has been "a real and reasonably clear disclosure": F. Hoffman-La Roche & Co. v. Commissioner of Patents [1971] HCA 3; (1971) 123 CLR 529, at p 539 . Here there was, I conclude, such a disclosure. The guidance provided by Lloyd-Jacob J. in Re Mond Nickel & Co. Ltd.'s Application (1956) RPC 189, at p 194 as to the meaning of "fairly based", when applied in comparing the Danish application with the letters patent in suit, has satisfied me that the latter is fairly based upon matter disclosed in the former. (at p473)

43. The defendant made three distinct submissions each based upon one of the criteria referred to by Lloyd-Jacob J. It was said that claim 1 was not broadly described in the Danish application which was confined to a "toy building element" and did not extend to sets of elements or blocks, as does claim 1 ; however although the Danish claims are confined to individual elements the application makes repeated disclosure of whole sets of such elements. Again it was said that there was inconsistency between claim 1 and the Danish application since the former, unlike the latter, did not refer to any role played by the internal walls of blocks in the clamping process ; however the references in the Danish application which were relied upon do not, I think, create an inconsistency, they are no more than descriptions of particular clamping effects that may be obtained in certain preferred embodiments of the invention. To confine claim 1 to clamping effects produced without the operation of internal walls of blocks is not to involve any inconsistency with the Danish application. Finally it was said that claim 1 included as a characteristic of the invention a feature as to which the Danish application was silent, namely that two blocks, one with one primary and the other with one secondary projection, may be clamped together. It is true that the Danish application speaks of a plurality of projections ; however it also refers to the wide variety of mutually different positions in which two blocks may be assembled and one such position would quite obviously be a position involving only one primary and one secondary projection, the internal walls of one block providing the other necessary clamping surfaces, that being a function of the walls to which the Danish application specifically adverts. While the failure of claim 1 to refer to this function introduces difficulties, to other consequences of which I have already referred, there does not, I think, arise from it any lack of fair basing such as the defendant contended for. (at p474)

44. I accordingly conclude that claim 1 has properly had assigned to it a priority date earlier than the allegedly anticipating French letters patent. (at p474)

45. The defendant also contended that claim 1 was too wide since it claimed monopoly for a whole set of building blocks some only of which might incorporate the invention claimed. There seems to me to be no vice in this ; what is claimed is monopoly for sets in so far as they comprise at least some blocks having particular features invented by the patentee ; remove those blocks and the set will not infringe, include them and the set falls within the monopoly claimed. (at p474)

46. The defendant submitted that the invention lacked novelty and was obvious and relied upon evidence that clamping, as a method of holding two objects together by the use of the elastic property of materials, had long been well known. I accept, on this aspect, the submissions of counsel for the plaintiff that the evidence discloses that hitherto the interconnexion of two blocks by clamping, otherwise than by the simple male-female clamp, was not employed despite the great advantages which it possesses in the case of building blocks, as testified to by the success of the plaintiff's blocks. There is here, I think, no absence of novelty in the sense of anticipation of the claimed invention. As to obviousness it has been said that this is, in essence, "a kind of jury question" Allmanna Svenska Elektriska A/B v. Burntisland Shipbuilding Co. Ltd. (1951) 69 RPC 63, at p 70 and in the present case, having considered those earlier letters patent dealing with building blocks which are in evidence and also the evidence of the engineering experts called by the parties, I conclude that it was, before the present claimed invention, by no means obvious to those skilled in the art that building blocks could with advantage be linked together by the means referred to in claim 1. (at p475)

47. Concluding as I do that, although prima facie infringement has been established, the defendant has succeeded in establishing that claim 1 is invalid for the reasons stated, the plaintiff's action will be dismissed and, on the counterclaim, there will be an order that claim 1 be revoked. (at p475)

Sydney, 1973, October 30, 31; November 1; December 7. 7:12:1973

From this decision the plaintiff appealed to the Full Court.

The following written judgments were delivered :-

BARWICK C.J. and MASON J. This is an appeal by Interlego A.G. against the

dismissal by Stephen J. of its suit for infringement of claim 1 of its Australian letters patent No. 229,550 for an invention for "Improvements in and relating to toy building sets and building blocks" and against an order for revocation of claim 1 of the letters patent. The defendant in the suit was the respondent Toltoys Pty. Ltd. which, like the appellant, is a manufacturer of sets of toy building blocks. The respondent's blocks are known as "Toltoy Brix". (at p475)

2. His Honour arrived at a conclusion adverse to the appellant on two grounds : 1. that claim 1 was invalid because it claimed a monopoly in a method of clamping toy blocks which formed part of the prior art ; and 2. that claim 1 did not comply with s. 40 of the Patents Act 1952 (as amended) in that it did not define the invention and was not clear. (at p475)

3. The appellant's patent is for a set of interlocking toy building blocks adapted for assembly, unlike toy building blocks hitherto known, in a wide variety of combinations. The character of the appellant's invention is best understood by reference initially to the state of the prior art. (at p476)

4. As the specification itself acknowledges, two different sets of interlocking toy building blocks formed part of the prior art. One set comprised "hollow blocks open at one face and provided with projections (primary projections) . . . symmetrically disposed on the face opposite the open face". The primary projections, arranged in two parallel rows and in transverse pairs, were uniformly spaced apart in both directions. The overall dimension over each pair of projections approximated the width of the cavity of the block and the overall dimension over each row approximated the length of the cavity. The arrangement, which makes use of the walls of a block as a coupling agent, enabled two identical blocks to be interlocked in staggered or offset relation. (at p476)

5. The second set comprised hollow building blocks, also provided with primary projections on the side opposite the open face and with projections set in the open face (secondary projections) arranged coaxially with the primary projections, the arrangement being such that the primary projections were provided with recesses adapted to receive the ends of the secondary projections of another block - this being an example of what has been referred to as male-female clamping. (at p476)

6. The specification then concedes that the building blocks according to the appellant's invention comprise features of the two known sets of blocks but it observes that the mere juxtaposition of primary and secondary projections would not provide coupling means for interlocking adjacent blocks in a vast variety of combinations. It goes on to say that :

"in order to solve this problem the relative dimensions and

positions of the primary and secondary projections must be

interrelated in a specific manner and according to the main

characterising feature of the invention the positions and

dimensions of the secondary projections relatively to the positions

dimensions of the primary projections are such that, in a pair

of assembled blocks the lateral face or faces of at least one

primary projection of one block will be clamped against the

lateral face or faces of at least one secondary projection of the

adjacent block."

7. The illustrations described in the specification show primary projections placed between the walls and secondary projections of adjacent blocks or between secondary projections without the assistance of the walls of the adjacent block. The illustrations do not depict primary projections inserted into the recesses of secondary projections. The body of the specification refers to this method of assembly as presenting "an additional advantage when combined with the principal feature of the invention". (at p476)

8. The point is made that if the secondary projections are tubular it is of advantage if the cavity within the projection is substantially equal to the diameter of the primary projections. The known method of male-female clamping may then be used in association with the principal feature of the invention which consists in the arrangement of the primary and secondary projections. (at p477)

9. Immediately before the claims the specification states that :

"while all the elements of the building set according to the

invention are in the form of hollow blocks . . . open at one face

and while the side and end walls . . . do in most cases cooperate

with the primary and secondary projections in the interlocking

of two adjacent blocks, it is theoretically possible to omit said

side and end walls . . . In fact, two elements . . . consisting

each of a base plate a and primary and secondary projections

but having no side or end walls could be interlocked in various

positions."

"A toy building set comprising a plurality of hollow blocks

open at one face and adapted to be connected together by means

of projections extending from the bottom faces of said blocks,

and wherein some of the blocks are provided with at least one

projection (primary projection) at the bottom face opposite

the open face, and some of the blocks are provided with at

least one projection (secondary projection) arranged within the

cavity of the block, characterised in that the positions and

dimensions of the secondary projections relatively to the

positions and dimensions of the primary projections are such

that, in a pair of assembled blocks the lateral face or faces of at

least one primary projection of one block will be clamped

against the lateral face or faces of at least one secondary

projection of the adjacent block (28th January 1958)." (at p477)

10. When the specification is read as a whole it appears that the invention consists in a set of interlocking hollow blocks adapted to be assembled in a wide variety of combinations by reason of the new and distinctive coupling method which they incorporate, the coupling method depending upon the interrelationship in adjacent blocks of primary and secondary projections, so that when two blocks are connected together at least one primary projection will be "clamped against" at least one secondary projection. It is made clear that, although in most applications the new coupling method will be used in association with the side and end walls of a block, the new method could be applied without use of the walls, as, for example, in the case of a block having at least one primary projection when connected with a base plate having secondary projections. (at p477)

11. We venture to think that no one would conclude, on reading the specification as a whole, that the invention as described makes claim to a method of assembly of blocks which depends on the insertion of primary projections into the recesses of secondary projections in an adjacent block. However, the settled rule is that in ascertaining the width of a particular claim it is not permissible to vary or qualify the plain and unambiguous meaning of the claim by reference to the body of the specification (Welch Perrin & Co. Pty. Ltd. v. Worrel [1961] HCA 91; (1961) 106 CLR 588, at p 610 ). It is therefore necessary to examine the language of claim 1. (at p478)

12. The argument that it asserts a monopoly in what is acknowledged to have formed part of the prior art is based on the proposition that the words "face or faces" in relation to secondary projections designate internal surface or surfaces as well as those which are external. "Face" may mean surface but to our mind, when it is used in this sense it refers ordinarily to the external surface of an object or to the side which is presented outwards. It is not a word which is apt to describe an internal surface unless it is qualified by an appropriate adjective so as to indicate that it is the internal surface that is the subject of reference. The words "face or faces" as applied to primary projections must refer to external faces of those projections. There is, as we see it, no reason to suppose that the expression has a different meaning when applied to secondary projections. (at p478)

13. Other considerations point the same way. The claim does not specify hollow or solid secondary projections - either is permissible. With solid projections, assembly by the known method cannot be achieved. Resort to the body of the specification would reveal that tubular secondary projections are recommended, but at the same time it would reveal that assembly by the known method was not the subject of the invention as described. Next, the expression "clamped against" as applied to the face or faces of the secondary projection suggests that the primary projection is held against the external face of the secondary projection ; it does not immediately bring to mind the notion that the primary projection is inserted into a recess in the secondary projection. In our opinion, therefore, the claim, construed without reference to the body of the specification, is not invalid on the ground that it asserts a monopoly in part of the prior art. (at p478)

14. Even if the claim, construed in isolation, is not to be interpreted as we consider it should be interpreted, we cannot think that the expression "lateral face or faces", read in association with the words "clamped against", is necessarily to be read as signifying the internal surface of the secondary projection. If the expression is not clear it is then permissible to resort to the body of the specification to define or clarify the meaning of words used in the claim without infringing the rule that clear and unambiguous words in the claim cannot be varied or qualified by reference to the body of the specification (see Electric & Musical Industries Ltd. v. Lissen Ltd. (1938) 4 All ER 221 ; 56 RPC 23 ; Rosedale Associated Manufacturers Ltd. v. Carlton Tyre Saving Co. Ltd. (1960) RPC 59, at p 69 ). Once reference is made to the body of the specification, it is apparent that the expression is not used in the sense urged by the respondent. (at p479)

15. Read in isolation or in the light of those parts of the specification which precede it, claim 1, as we understand it, asserts a monopoly in blocks which incorporate the coupling method referred to in the claim and elsewhere described. It is a claim by reference to result in the sense that it indicates how the projections are placed when assembly takes place, and does not explicitly specify other means of clamping, that is, the use of the side and end walls of the blocks, when assembly takes place. (at p479)

16. The definition of the invention in the claim, which is framed by reference to the result achieved when assembly takes place, lends itself to criticism in that it does not state explicitly the means by which at least one primary projection is to be clamped against at least one secondary projection. The claim is expressed in the language of the statement of the principal feature of the invention contained in the body of the specification. Although the claim does not set out the detailed explanation of the invention contained in the body of the specification, it is to be understood in the light of that explanation. When it is so read, the reader will perceive that, when two blocks are assembled, a single primary projection will be kept in place against a single secondary projection by the wall or walls of the block containing the secondary projection, and that when there is more than one secondary projection the primary projection will be kept in its appointed place by the walls of the other block or by another or other secondary projections. (at p479)

17. There are two specific objections to the definition attempted by the claim. One objection is that it actually negatives participation by the walls of a block in the coupling process. For our part, we do not so understand the claim. It deals with the assembly of blocks described as "hollow blocks", thereby bringing to mind the circumstance that the walls, in accordance with what has already been said, will provide co-operative assistance in that assembly. (at p479)

18. The second objection is that the claim is wide enough to embrace a coupling method not disclosed in the specification (e.g. a clip) which would keep a primary projection in its appointed place. Again, we do not agree with this interpretation of the claim. It speaks of "hollow blocks . . . adapted to be connected together by means of projections", indicating that it is confined to methods of clamping effected by means of the characteristics to which it refers, including among them the walls of the hollow blocks. (at p480)

19. The claim asserts a monopoly limited by reference to the result of incorporating in the construction of the hollow blocks the suggested relationship between primary and secondary projections, the result being that at least one primary projection is "clamped against" at least one secondary projection. It is permissible to limit a claim by reference to result (see No-Fume Ltd. v. Frank Pitchford & Co. Ltd. (1935) 52 RPC 231 ), so long as, in the case of an article, the limitation is "sufficient to characterize the construction of the article claimed" (Mullard Radio Valve Co. Ltd. v. British Belmont Radio Ltd. (1938) 56 RPC 1, at p 16 ). As we have observed, the claim is in our opinion sufficiently limited. (at p480)

20. Apart from the two grounds of invalidity already considered the respondent submitted that the appellant's patent was invalidated on the grounds of prior publication and prior user. The first ground taken was based on the disclosure of an invention in a French patent no. 1,141,279, deposited in the Patent Office Library at Canberra on 6th February 1958, nine days later than the priority date assigned to the first claim in the appellant's patent by the Patents Office, namely, 28th January 1958. The Commissioner for Patents evidently concluded that the first claim was fairly based on matter disclosed in the Danish basic application of 28th January 1958, one of several Convention applications on which the appellant's Australian application was based (see ss. 141,142). The respondent sought to displace the assigned priority date by showing that claim 1 was not "fairly based on matter disclosed" in the Danish application within the meaning of s. 142 (4). We are prepared to assume, without so deciding, that the respondent's argument on this point is correct, as we have come to the conclusion that the French patent in any event is not a prior publication of the appellant's invention. (at p480)

21. The invention disclosed in the French patent consists of a set of hollow blocks so manufactured that the length of each block is approximately double its width. A transverse partition is placed half-way along the length of the block so as to divide the cavity into two equal square spaces. On the opposite side of the block are two male insertion elements, each constituted by a cross-shaped profile with four branches which fit into the square cavities of the adjacent block. If the transverse partition is to be regarded as a secondary projection, each block contains but one, whereas the appellant's invention contemplates that the secondary projections will not necessarily be so limited in number. What is of more importance is that the transverse partition is something different from the appellant's concept of a secondary projection. The partition is an internal wall which divides the cavity of a block into two equal spaces ; the secondary projection performs no such function. There is also lacking in the French patent that arrangement of primary and secondary projections having an interrelationship in position and dimension which is characteristic of the appellant's invention. For these reasons we do not regard the French patent as a prior anticipation. (at p481)

22. Next, it is said that the development from the French patent to the appellant's invention was obvious. In the light of the discussion which has already taken place this submission has little force. As we see it, the French patent did little more than capitalize on the known method of assembly which involved the fitting of primary projections on one block within the cavity of another block ; by providing the transverse partition it divided the cavity of a hollow block into two equal spaces and thereby enabled staggered or offset connexion to take place in several positions. To our way of thinking the provision of the transverse partition did not point in the direction of a method of assembly based on the interrelationship of primary and secondary projections of the kind proposed by the appellant's invention. (at p481)

23. The respondent then relied upon the sale in Australia prior to 28th January 1958 of toy blocks known as "Bilda Brix". It is common ground that they were widely sold in this country before that date. "Bilda Brix" are hollow blocks having primary and secondary projections adapted to be assembled one on top of the other with the primary projections of the lower block fitting into recesses in the secondary projections of the adjacent upper block. It so happens that some, but not all, of the blocks may also be assembled by means of clamping the primary projections in the spaces between the secondary projections and the walls of the block. The circumstances in which "Bilda Brix" were marketed were not proved in evidence. There is no evidence which would suggest that the manufacturers or distributors asserted that one of the qualities of the product was a capacity for assembly in a staggered or offset relation. Indeed, the fact that some blocks are not adapted to that method of assembly would indicate that they were neither regarded, nor held out, as being adapted to assembly in this fashion. (at p482)

24. In the absence of evidence of this kind we would not be justified in inferring that the sale of the blocks gave rise to a prior publication or a prior user in a manner unfavourable to the appellant's case. Whether the blocks were ever assembled in staggered or offset fashion seems to us to be a matter of speculation and no more. Moreover, even if the blocks were so assembled before 28th January 1958 there is nothing to indicate whether that use was other than accidental and minimal. Prior use, in order to invalidate a patent, must be a use which is more than accidental and experimental (see Bristol-Myers Co. (Johnson's) Application (1973) RPC 157, at pp 165-166 ). Consequently, the objections which are based on the sale of "Bilda Brix" fail. (at p482)

25. There is finally the question of infringement. Although this issue was virtually conceded by the respondent at the hearing of the action, the point now taken by the respondent is that its product does not involve assembly by means of secondary projections. The respondent's blocks have primary projections of the kind recommended in the appellant's patent ; indeed, they are of the same dimensions and spacing as the primary projections in the appellant's "Lego" blocks. However, in lieu of the tubular secondary projections recommended in the appellant's patent, the respondent's "Toltoy Brix" are equipped with partitions running diagonally across the cavity of the hollow block, dividing the cavity into a series of small compartments into which the primary projections of an adjacent block will fit. If it be proper to style the diagonal partitions as secondary projections "arranged within the cavity of the block", when the blocks are assembled the lateral face of at least one primary projection is clamped against the lateral face of at least one secondary projection, with the consequence that the respondent's product infringes the appellant's patent. In our opinion the diagonal partitions of the respondent's product may be described accurately as secondary projections "arranged within the cavity of the block". (at p482)

26. Consequently, in our view the appellant has established that the respondent infringed its patent and is entitled to relief accordingly. The counterclaim for revocation of claim 1 of the letters patent should be dismissed. (at p482)

MENZIES J. This is an appeal from a judgment of Stephen J. in favour of the defendant in a patent action. The plaintiff (Interlego) sued the defendant (Toltoys) for infringement of Australian letters patent No. 229, 550 relating to "improvements in and relating to toy building sets and building blocks" relying exclusively upon claim 1 of the complete specification. The defendant counter-claimed for revocation on various grounds. The action was dismissed and claim 1 was revoked. (at p483)

2. There were two grounds for his Honour's decision to revoke claim 1. The first was that the claim was expressed so widely as to include as part of the monopoly claimed that which was not novel and had, indeed, been described in the body of the specification as part of the prior art. The second was that the claim did not comply with s. 40 (1) of the Patents Act in that it did not define the invention described in the body of the specification. His Honour rejected a submission that the claim was invalid either by reason of obviousness or lack of novelty in the sense that it had been anticipated by earlier articles or published material. In the course of his decision that the invention had not been anticipated, his Honour had no regard to French letters patent 1,141,279, first open for inspection in the Canberra Patent Office Library on 6th February 1958, because of his conclusion that the priority date of claim 1 was 28th January 1958. His Honour held that the application being a convention application was fairly based upon matter disclosed in the basic application, viz. a Danish patent application of 28th January 1958. His Honour accordingly did not consider the question whether the French letters patent would have constituted an anticipation of what is claimed in claim 1. (at p483)

3. His Honour thought that, prima facie, infringement had been established. (at p483)

4. Upon this appeal it was contended on behalf of Toltoys, that, not only was his Honour correct in deciding that claim 1 was invalid upon the two grounds on which the decision was based, but also, that the claim was invalid because it had been anticipated and it was obvious. In so submitting counsel for Toltoys challenged the finding that the priority date of claim 1 was 28th January 1958, contending that the application for the patent in question was not fairly based upon the Danish application of that date. This was preliminary to a reliance upon the French letters patent No. 1,141,279 as an anticipation and as matter making the invention claimed obvious. Furthermore, counsel for Toltoys contended that the invention was not novel because of the sale in Australia, prior to 28th January 1958, of building blocks known as "Bilda Brix". Finally it was contended that the blocks sold by Toltoys did not infringe claim 1 of letters patent No. 229,550. (at p483)

5. I propose to examine, in the first place, his Honour's reasons for deciding that claim 1 is invalid. (at p483)

"1. A toy building set comprising a plurality of hollow

blocks open at one face and adapted to be connected together

by means of projections extending from the bottom faces of

said blocks, and wherein some of the blocks are provided

with at least one projection (primary projection) at the bottom

face opposite the open face, and some of the blocks are provided

with at least one projection (secondary projection) arranged

within the cavity of the block, characterised in that the

positions and dimensions of the secondary projections relatively

to the positions and dimensions of the primary projections are

such that, in a pair of assembled blocks the lateral face or faces

of at least one primary projection of one block will be clamped

against the lateral face or faces of at least one secondary

projection of the adjacent block (28th January 1958)."

What is there defined is a set of toy building blocks - two at least - which can be connected together. Each is a hollow block with a top open face. Each has projections from its bottom face - primary projections - and of these primary projections one at least will, in assembly with an adjacent block, have a lateral face clamped against the lateral face of at least one secondary projection arranged within the cavity of the adjoining block. These secondary projections are projections from the floor of the cavity of the block extending towards its open face. The clamping depends upon the positions and dimensions of the secondary projections of one block relatively to the positions and dimensions of the primary projections of another block. No further definition is attempted. A block may be of any material ; it may be of any size ; it may have any number of primary projections. Not every block must have secondary projections, but a block which has secondary projections may have one or more of such projections. The size, shape and arrangement of the primary projections are not specified. The size, shape and arrangement of any secondary projections are not specified. All that is specified with regard to the projections is that, upon the assembly of two adjacent blocks, "the lateral face or faces of at least one primary projection of one block will be clamped against the lateral face or faces of at least one secondary projection of the adjacent block". The invention is defined by a result to be achieved in a stated manner. There is no reference to the walls of any block - apart from the description "hollow blocks" - and in particular the clamping which is to occur upon assembly is not stated to be due to the positions and dimensions of the walls relatively to the positions and dimensions of either the primary or, where they exist, the secondary projections. Indeed, the claim, as it is framed by the express reference to the positions and dimensions of the projections, would seem to negative according to the positions and dimensions of the side walls of the hollow blocks, any part in the result to be achieved. (at p485)

7. It is obvious that two blocks, each without secondary projections, cannot, in accordance with what is defined, be assembled together ; the clamping effect is made to depend upon the relative positions and dimensions of primary and secondary projections. (at p485)

8. Furthermore, it is obvious that if one block has but one primary projection and another block has but one secondary projection, the clamping to effect their connexion could be achieved in but one of two ways, First, by the engagement of a primary and a secondary projection by one fitting into the other so that the external lateral face of one is clamped by being met with the internal lateral face of the corresponding open projection. Alternatively, by engaging the projection of one block between a wall and a projection of the adjacent block so that the two would form a clamp for the intruding projection from the other block. (at p485)

9. If the claim does cover the first method of achieving a connexion between blocks, where one has but one secondary projection, it is invalid because such a method of assembling blocks was well known before the priority date of claim 1. Indeed, in the body of the specification this is expressly stated as follows :

"Moreover, in another type of hollow building blocks which

are likewise provided with outwardly extending projections on

the side opposite the open face there are provided inwardly

extending projections arranged co-axially with the outwardly

extending projections, the arrangement being such that the

outwardly extending projections are provided with recesses

adapted to receive the ends of the inwardly extending

projections of another block."

10. Stephen J. held that the claim does, upon its proper construction, cover such a method of connexion, and if his Honour was correct in so construing the claim that would be an end to the matter. A patentee is not entitled to a monopoly for what is acknowledged to be and is old. (at p485)

11. In considering the correctness of his Honour's decision on this point, it is, I think, legitimate to construe a claim in a specification which refers to prior art as, prima facie, not intending to encompass what belongs to that prior art within the definition of the invention claimed. See Welch Perrin & Co. Pty. Ltd. v. Worrel (1961) 106 CLR, at pp 593, 610, 614 . If, however, upon the proper construction of a claim, what was prior art is found to be within the definition of the invention claimed, the patent will be invalid. It matters little how it came about that what was old has been claimed as comprehended by the invention for which a monopoly is sought. (at p486)

12. Accordingly, the question is whether claim 1, upon its proper construction, does cover a connexion by means of a projection from one block fitting into a recess in an adjacent block upon assembly. Put more precisely, the problem is whether, when a primary projection is forced into a recess in a secondary projection so that it holds there by virtue of the elasticity of the projections, what occurs is the clamping of the face of one against the face of the other projection, For the purposes of examining this problem, the complexity resulting from various shapes that a projection may take can be legitimately avoided and the simple course followed of taking two circular projections, the secondary projection being tubular into which the primary projection can be forced so that it will hold until disengaged. If the invention as defined covers this method of making a connexion between two blocks of the sort described, then it follows that the claim includes in its definition of the invention blocks belonging to the prior art which would, upon the grant of the patent - if valid - become infringing articles. (at p486)

13. As a matter of first impression, the language of the claim hardly amounts to an apt description of the method of connexion which I am considering, but it must be kept in mind that the language of the claim is intended to cover a wide range of means providing for the connexion of a number of blocks and it may be that it is of little importance that the language used would not constitute a very apt description of something within that range if it merely stood by itself. An impression cannot be decisive ; the language of the claim does, I think, require close examination. First, does the exterior face of a column fall within the description of "a lateral face" simply because it is a side face? I think it does. Secondly, does the interior face of a tube fall within the description of "a lateral face"? Again I think it does. A tube has an inside face as well as an outside face, and if one is lateral so is the other. Accordingly to push a column into a tube so that it is held within the recess does bring two lateral faces of the projections together. The next question is whether the lateral face of the column so held should properly be described as "clamped" against the lateral face of the tube. In the context of the claim the word "clamped" does, I think, import that the clamping action is to depend upon the force used in the assembly of two blocks and not upon their being held together by the pressure of some separate clamp, such as a band which could be tightened around them. Accordingly, to force a primary projection between two secondary projections so that the connexion would hold until the projections are disengaged, would result in the kind of clamp to which the claim relates. There is, however, only one arrangement in which one primary projection could engage with one secondary projection and nothing else, i.e. by forcing one into the other so that the inside projection is clamped in the outside projection as is a cork in a bottle. (at p487)

14. The claim unquestionably contemplates that there may be but one primary projection in engagement with one secondary projection. This follows from the insistence 1. that the engagement may be merely one with one face to another face, and 2. that the clamp must always depend upon the relative positions and dimensions of the projections. Accordingly I have, with some hesitation, come to agree with the first ground upon which Stephen J. decided that the claim is defective. His decision is, I think, supported by the evidence to which he refers, and which I will not repeat, relating both to what an engineer would understand by the words "lateral face" and "clamped". (at p487)

15. It seems to me, moreover, that there is a real link between this ground and his Honour's second ground, i.e. that the claim does not define the invention, for unless the claim covers the insertion of a projection from one block into a projection from another block the claim does not define that part of the invention covering the clamping of one lateral face of one projection against one lateral face of another projection in an adjacent block. The claim, as has already been observed, insists that the clamping is to follow from "the positions and dimensions of the secondary projections relatively to the positions and dimensions of the primary projections". This I treat as exhaustive and as leaving no room for the introduction of some other means of clamping such, for instance, as by reason of the positions and dimensions of a wall of a block relatively to the positions and dimensions of the primary or secondary projections. Accordingly the invention cannot be defined by introducing the walls as a means of ensuring the essential result, namely that the lateral face of a primary projection would be clamped against the lateral face of a secondary projection. (at p487)

16. The defect which I find in claim 1, viz. that it does not define the invention, cannot be overcome by the principle applied by the Court of Appeal in No-Fume Ltd. v. Frank Pitchford & Co. Ltd. (1935) 52 RPC 231 , which was a case dealing with insufficiency. There it was decided that an invention may be defined by reference to the result, and the shapes and dimensions requisite to produce the result need not be defined if the dimensions are sufficiently described as to be ascertainable by tests not involving the exercise of any inventive faculty. That decision could perhaps be invoked to answer a contention that the words in claim 1 "the positions and dimensions" of the projections do not provide sufficient information. The principle cannot, however, save a specification that does not define an alleged invention because the language of the claim impliedly excludes a necessary element from consideration. What Romer L.J. said is relevant here (1935) 52 RPC, at p 243 :

"It is essential to the validity of a patent that the complete

specification should sufficiently and fairly describe and ascertain

the nature of the invention and the manner in which the

invention is to be performed : in other words, that the patentee

should disclose his invention sufficiently to enable those who

are skilled in the relevant art to utilize the invention after

the patentee's monopoly has come to an end. Such disclosure

is, indeed, the consideration that the patentee gives for the

grant to him of a monopoly during the period that the patent

would run. Another essential to the validity of the patent is

that the complete specification should sufficiently and clearly

ascertain the scope of the monopoly claimed. The reason for

that is in order that those who are engaged in the art may

know how far they can go without running the risk of having

an action for infringement of the patent started against them

by the patentee. If the complete specification does not clearly

indicate the ambit of the invention, it will redound, to use the

words of s. 6 of the Statute of Monopolies, 'to the hurt of trade,

and be generally inconvenient'. One might put it a great

deal more strongly - the patent will be a public nuisance,

hindering and embarrassing those persons engaged in the

particular art, from carrying on their legitimate trade or

business."

It is this second essential that I find lacking in claim 1. It matters not, therefore, that a skilled workman might, without inventive skill, arrange one projection in such a relationship with a side wall of the cavity of a block that the two could operate to clamp a projection from another block, for such a clamping is outside the definition of the invention. (at p488)

17. The possibility did occur to me that the specification might be read as requiring that every block to which it relates must have a plurality of primary projections. Were this so, it could, of course, be arranged that one secondary projection could be clamped between two or more primary projections. Such a reading of the claim would, of necessity, exclude a block with one primary projection only from the ambit of the claim. Counsel for the appellant rejected such a construction as a possible reading of the claim and did so, no doubt, for good reason. I, of course, accept that rejection and decide the case without regard to the possibility of so construing claim 1. (at p489)

18. In short, therefore, it appears to me that what is claimed, to the extent that it covers the engagement of one primary projection with one secondary projection, can be achieved in but one of two ways : first, by the insertion of one projection in the other ; secondly, by the use of a side wall of the block in conjunction with projections to achieve a clamping effect. If the first possibility is covered by the claim it is bad because something included in a claim for a monopoly is old. Of the second possibility there is no hint ; indeed, the assertion that the engagement depends upon the relative positions and dimensions of the projections themselves excludes it from consideration. (at p489)

19. Accordingly, because I agree with Stephen J. that claim 1 is invalid for the reasons which he has given, it is unnecessary for me to consider the other submissions of the appellant. (at p489)

20. I would, for the foregoing reasons, dismiss the appeal. (at p489)

Orders made by Stephen J. set aside. In lieu thereof order -

1. That the respondent by itself, its servants and agents be restrained from infringing the appellant's Letters Patent No. 229,550 during the continuance or any extension thereof.

2. That it be referred to a Justice of this Court to inquire as to what profits have been made by the respondent by reason of its infringement of the appellant's said Letters Patent.

3. That the respondent pay to the appellant the amount ascertained in the said inquiry.

4. That the appellant have liberty to apply for an order for delivery up of infringing articles.

5. That the respondent pay the appellant's costs of the action and counterclaim.