L.J., in his book on Partnership (u): "In the case of a patent belonging to several persons in common, each co-owner can assign his share, and sue for an infringement (x); and can also work the patent himself, and give licences to work it, and sue for royalties payable to him for its use (y); and it is now settled that he is entitled to retain for his own benefit whatever profit he may derive from the working, although it is perhaps still open to question whether he is not liable to account for what he receives in respect of the licences "(z).

The grounds upon which one co-owner can sue for infringement of the patent without joining the other co-owners are clearly set out in the judgment of Page-Wood, V.-C., in Dent v. Turpin (a); the law as therein expressed is that although he may sue alone, the Court will not grant a decree for further relief than that which is purely personal to himself, that is to say, he may have an injunction against the infringer, but he will only receive that portion of the damages to which the Court may think he is entitled; this would seem to show that he is only entitled to such portion of the damages as bear a relation to his interest in the patent.

In Smith v. L. & N. W. Ry. Co. (b), it was decided that the right of co-owners to damages for infringement was a joint right and on the death of one the survivor was entitled to recover the whole.

Where a sole patentee worked the patent in partnership with another for some years during which time they were extensively advertised as joint patentees, it was held that the partner of the sole patentee thereby acquired such an interest in the patent as to enable him to work it independently after the partnership had expired (c), but this would not be the case if it were a term of the

(u) 5th ed. p. 62.

(x) Dunnicliffe v. Mallett, 7 C. B., N. S. 209; Dent v. Turpin, 2 J. & H. 139; 30 L. J., Ch. 495; Sheehan v. Great Eastern Railway, L. R., 16 Ch. D. 59, 63.

(y) Sheehan v. Great Eastern Railway, L. R., 16 Ch. D. 59.

() Mathers v. Green, L. R., 1 Ch.

29; Russell's Patent, 2 De G. & J. 130.

(a) 2 J. & H. 139; 30 L. J., Ch. 495, 496.

(b) 2 El. & Bl. 69, 74; 17 Jur. 1071; Macr. P. C. 188, 207.

(c) Kenny's Patent Button-Holeing Co. v. Somervell, 38 L. T. 878; 26 W. R. 786.

partnership that the patent rights in the invention should belong exclusively to one of them (d).

A mortgagee registered as such at the Patent Office has not such an interest in the patent as to be a necessary party to an action for infringement, since the mortgagor and not the mortgagee is the person for the time being entitled to the benefit of the patent, and consequently in the same position as the mortgagor of any other property whether real or personal (e).

Fraudulent agreements for the assignment of patents, such, for instance, as bubble patents, will be set aside (ƒ). But in the absence of fraud the agreement will be enforced, and it is no defence to the action that the plaintiff has not invented the alleged invention (g).

Licences differ from assignments, in that the patentee granting a licence does not part with his whole interest, but grants merely a right to use the patent for the whole term or any portion of the whole term, that is merely a right to do that which without a licence could not be done except by violating the monopoly granted to and still vested in the licensor (h).

Sect. 22 of the Act of 1883 provides for the granting of compulsory licences.

"If on the petition of any person interested it is proved to the Board of Trade that by reason of the default of a patentee to grant licences on reasonable terms

or,

"(a) The patent is not being worked in the United Kingdom;

(b) The reasonable requirements of the public with respect to the invention cannot be supplied; or

(c) Any person is prevented from working or using to the best advantage an invention of which he is possessed, the Board may order the patentee to grant licences on such terms as to the amount of royalties, security for payment or otherwise, as the Board, having

(d) Axmann v. Lund, L. R., 18 Eq. 330, 336.

(e) Van Gelder Apsimon & Co. v. The Sowerby Bridge Flour Society, 7 P. O. R. 208; Fairclough v. Marshall, L. R. 4 Ex. D. 37.

(f) Lovell v. Hicks, 2 Y. & C. 46.

(g) Smith v. Buckingham, 18 W. R.

314.

(h) Heap v. Hartley, 6 P. O. R. 495, 500; see also Muskett v. Hill, 5 Bing. N. C. 694, 707; Thomas v. Sorrell, Vaugh. Rep. 351; Newby v. Harrison, 1 J. & H. 393; 3 De G. F. & J. 287.

regard to the nature of the invention and the circumstances of the case, may deem just, and any such order may be enforced by mandamus."

These provisions are entirely novel; (a) and (b) are capable of being reasonably construed; as to "(e)" it is difficult to understand how the Board of Trade will come to a decision as to whether "a person is prevented from working or using, to the best advantage, an invention of which he is possessed." The "invention" must be protected by letters patent (see the construction given in sect. 46).

The proceedings under sect. 22 are regulated by Patent Rules, 1890, rr. 60-66.

A licence granted by the patentee may be exclusive or otherwise, that is, it may be a grant of the sole right to put the invention into practice, or of a right limited in time or in area, or of a right only to be exercised in conjunction with others; but as has been pointed out above, à licence, even though it may be exclusive, does not convey such an interest in the patent as to amount to an assignment of it.

Licences should be under seal, the prohibition in the grant itself being "without the consent, licence or agreement of the said patentee in writing under his hand and seal."

A licence granted by a patentee, but not under seal, is, however, not void in the sense that the licensee, having used the patent, is not bound to pay the royalties contracted for. In Chanter v. Dewhurst (i), it was held that the defendants, having obtained the licence they had bargained for, and kept it, were bound to pay for it; and secondly, that the licence was not void as not being under seal. Baron Alderson said: "The defendants, in making the machine in question, are merely acting as agents for the patentee. . . . in my opinion a licence for this purpose need not be under seal."

Although the words of the grant are "under his hand and seal," the document is not a deed, since it need not be delivered as a deed, nor need it be stamped as such (k).

In the absence of fraud money paid by a licensee for royalties.

cannot be recovered when it is ascertained that the patent was void ab initio (1). And if the licensees have kept the licence and used it, the licensor can recover from them the agreed royalties, although the patent may have been void and the licence not under seal (m); but otherwise, if the licensor knew from the first that the patent was void (n). But if the consideration for the money paid is that an application for a patent should be made and a licence to use the patent granted, no application being made for the patent, there is a total failure of consideration, and the price paid may be recovered (o). A licence is not assignable (p). A licence to a man and his assigns means a licence with power to licensee to sub-license (idem). A licensee may covenant not to manufacture without applying the patented invention; such a covenant is not in restraint of trade (q). A patentee having granted a licence cannot prevent anyone vending the articles which have been made in pursuance of the licence (r). And an inventor selling the patented article abroad cannot restrain its importation and sale in this country, although an assignee of the patent in this country might restrain the importation of an article made by the original inventor or his assignee abroad (8).

An exclusive licensee of an invention for a district cannot maintain an action against one who, having purchased a thing which was the subject-matter of the invention, should bring his purchase within such district without notice of the licence (t); registration at the Patent Office does not amount to notice to the whole world (ibid.). A latent ambiguity in a licence by deed may be explained by parol evidence in the same manner as other deeds (u). A licensor may in the licence deed stipulate for a

(1) Taylor v. Hare, 1 B. & P. (N. R.) 260.

(m) Chanter v. Dewhurst, 12 M. & W. 823.

(n) Chanter v. Leese, 4 M. & W. 295.

(0) Knowles v. Bovill, 22 L. T., N S. 70.

(p) Per Maule, J., in Bower v. Hodges, 22 L. J., C. P. 198.

(q) Jones v. Lees, 1 H. & N. 189

(r) Thomas v. Hunt, 17 C. B., N. S. 183.

(s) Betts v. Willmott, L. R., 6 Ch. 239; see also Société Anonyme v. Tilghman, L. R., 25 Ch. D. 1; 53 L. J., Ch. 1; 49 L. T. 451; 32 W. R. 71; Heap v. Hartley, 5 P. O. R. 610.

(t) Heap v. Hartley, 5 P. O. R. 603; 6 P. O. R. 495.

(u) Roden v. The London Small Arms Co., 46 L. J., Q. B. 21

forfeiture in the event of royalties not being paid (x), but such forfeiture may be waived (y). The licensor may also agree that he will take all necessary steps to support the validity of the patent (2).

A licence may be created by parol (a), but whether by parol or under seal, if there is no time fixed for its duration (b), and no term in the licence which would necessitate a different construction (c), it may be determined at will by either party. In Mills v. Carson (d), the patentee granted by deed an exclusive licence to the defendant for the remainder of the term of the patent, in consideration of which the defendant agreed to pay 1007. per annum for the remainder of that term, such a condition was held to be totally inconsistent with a licence revocable at will. Express notice to revoke must be given, and the mere plea that the licence has been abandoned is not in itself sufficient (e).

A licensee cannot sue alone for infringement of the patent, and this would appear to be so even in the case of an exclusive licensee (f), who must sue either in the name of the patentee (g), or be joined with the patentee as co-plaintiff.

In Renard v. Levinstein (h), the licensees and the owners of the patent were joined as co-plaintiffs; while the action was pending, the owners parted with their interest to a third party; under these circumstances Wood, V.-C., overruled the objection that the plaintiffs did not show sufficient interest to maintain the action.

(x) Tielens v. Hooper, 5 Exch. 830. (y) Warwick v. Hooper, 3 M. & G. 60.

(z) Henderson v. Mostyn Copper Co., L. R., 3 C. P. 202.

(a) Crossley v. Dixon, 10 H. L. Cas. 293; L. J., 32 Ch. 617, H. L.; Chanter v. Dewhurst, 12 M. & W. 823; 13 L. J., Ex. 198; Post Card Automatic Supply Co. v. Samuel, 6 P. O. R. 560.

(b) Crossley v. Dixon, 10 H. L. Cas. 293; Redges v. Mulliner, 10 P. O. R. 21, 27; Cheetham v. Nuthall, 10 P. O. R. 321, 333; see also Wood v.

Leadbitter, 13 M. & W. 838; 9 Jur. 187; 14 L. J. Ex. 161.

(c) Ward v. Livesay, 5 P. O. R. 102, 106; Guyot v. Thomson, 11 P. O. R. 541, 554.

(d) 9 P. O. R. 338; 10 P. O. R. 9. (e) Cheetham v. Nuthall, 10 P. O. R. 321, 333.

(f) Heap v. Hartley, 6 P. O. R. 495, 500; Renard v. Levinstein, 2 H. & M. 628; Barnett v. Barrett, 1 P. O. R. 9; see also Woolley v. Broad, 9 P. O. R. 208.

(g) Heap v. Hartley, at page 501. (h) 2 H. & M. 628.