the fourth. This was refused, because it reflected on Melling's patent, and there was no evidence that the earlier patent had the alleged disadvantages.

On appeal, the applicants were not allowed to file such evidence, having accepted the decision.

The Law Officer struck out the first part of the fourth amendment, and substituted the words: "We do not claim the casting of steel ingots simultaneously through centrally situated nozzles or outlets." No costs to either side.

Serrell's Patent, 6 R. P. C. 101.

A patent (No. 14983 of 1886) was granted for the "application of a solenoid for reinforcing electrical contacts." The invention was described as consisting "in reinforcing the actual contact between two contact-pieces of an electric circuit, by means of a solenoid." The drawings showed a contact consisting of one part movable horizontally, to which was attached an arm, bearing on its end a contact surface, C, rounded (in section) in an arc of about 60°. The other surface, C', was semicircular in section, and attached to the end of an arm hinged and pressing against a spring. On the arm being moved horizontally, the first quadrant, C, rubbed against the second arm, the round contact-pieces, CC', sliding against each other. The solenoid, X, surrounded part of the horizontal part, so that when the current began to pass the solenoid drew the sliding part closer against the hinged portion.

The claim was for "the employment of a solenoid X and core A, for the purpose of reinforcing the contact between the contact-pieces CC' of an electrical circuit."

Amendments were asked to (a) alter the title to "Improvements in electrical contact devices; (b) to describe the invention as "an improved electrical contact device, the main purpose of which is to keep the contact-pieces clean ;" and (c) to alter the claim to "the production of a scraping, and consequently cleaning, motion between the contact-pieces CC', by means of magnetic attraction created by the current passing between them, after said contactpieces have been made to touch in any known manner.” The amendments as proposed were refused by the Comptroller and Law Officer. The Law Officer permitted the insertion of the words "in the manner hereinafter described " after the words "by means of a solenoid" (supra), and the variation of the claim so that it should read, "The employment of a solenoid X and core A for reinforcing the contact between the contact-pieces CC' of an electrical circuit in the manner hereinbefore described." Webster, A.G.: “I think it would be beyond what is intended by the power of amendment under the Act of 1883, that there being a

distinct and specific claim to the operation of what is believed to be new, and there being no claim to the minor arrangement of the contact-pieces, the patentee should be allowed to strike out the whole of his claim, and insert an independent claim to a subordinate part. It is said this is justified on the ground that the patentee is afraid the patent would be held invalid, because Hedges, in a previous specification" (No. 719 of 1883) "has disclosed a method of reinforcing the contact by the action of a solenoid. As to that no amendment would make the claim good, and at any rate it is not the proper form of amendment to effect that purpose. The only way of dealing with it would be by, on the face of it, disclaiming what I may call the general use of solenoids and cores, and applying it to the particular mode herein described. It is for that reason, and because I think no harm will be done to the public, that I am willing, as part of my judgment, to allow the applicant to have a disclaimer in the form I have already indicated."

Johnson's Patent, 13 R. P. C. 659.

The specification (No. 6626 of 1885) was for the manufacture of saccharine. The specification described this new sweet compound as "anhydro-ortho-sulphamine benzoic acid" or "benzoic sulphinide," and the inventors called it saccharine.

Two methods of manufacture were described. The first consisted in converting, by a series of reactions, a mixture of two isomeric toluene-monosulphonic acids into the corresponding isomeric ortho- and para-sulphochlorides. The para compound was a solid, and was separated by means of a centrifugal machine. Directions were given for removing "the last traces" of it by cooling and again using the machine. The ortho compound was liquid, and when further operated on as directed produced anhydro-orthosulphamine benzoic acid or benzoic sulphinide. A second method was also described.

The first claim was: The process described as the first method for manufacturing anhydro-ortho-sulphamine benzoic acid or benzoic sulphinide or saccharine with employment of one or all of the reactions set forth in the specification.

The second, third, and fourth claims related to the second process. The fifth and sixth claims were for the "production of anhydrous-orthosulphamine benzoic acid or benzoic sulphinide or saccaharine" having the properties, and by means of the methods, described. The proposed amendments consisted in: (a) minor corrections and the excision of the second method and its claims; (b) the excision of the words "anhydro-ortho-sulphamine benzoic acid or benzoic sulphinide or" from the other claims and corresponding parts of the

specification; (c) the substitution of the words "as much as possible" for "the last traces" in the directions as to removing the para compound; (d) the insertion of words showing that the sweet compound was not quite pure as implied in the specification; and (e) after the word "saccharine" the insertion of the following words: "but as its sweetening qualities depend solely on the presence of anhydroortho-sulphamine benzoic acid (it being a mixture of the same with an inert body, viz. para-sulphamine benzoic acid), the name 'saccharine' is also applied by them to that substance when isoIn this specification the word will be used only for the mixed body, the other being designated by its scientific name," and the addition of a statement to the reactions.

The learned Law Officer rejected the chief amendments, being satisfied that the inventor did not at the date of the specification know of the presence of the inert para body in his saccharine; “. . . disclaimer is not to be used solely for the mere purpose of turning an insufficient description into a sufficient description. Of course it is to be used for the purpose of turning an ambiguous specification into a clear specification, but not for the purpose of turning an insufficient description into a sufficient description, especially if the amendment introduces subsequent knowledge." The substitution of the words "as much as possible" for the last traces was allowed, also the minor amendments and excision of the second process (a and c).

Amendment during Legal Proceedings.

When an action for infringement or a petition for revocation is pending, the specification can only be amended by obtaining leave of the Court. An application to amend by way of explanation or correction made to the Comptroller under sect. 18 is not suspended or stayed by reason of the subsequent presentation of a petition for revocation before the hearing by the Comptroller. Where there are more actions than one, or a petition and an action, leave need not be obtained in each proceeding before any amendment can be made. The provisions on the subject are contained in sect. 19 of the Act of 1883

19. In an action for infringement of a patent, and in a proceeding for revocation of a patent, the Court or a judge may at any time order that the patentee shall, subject to such terms as to costs or other

wise as the Court or a judge may impose, be at liberty to apply at the Patent Office for leave to amend his specification by way of disclaimer, and may direct that in the meantime the trial or hearing of the action shall be postponed.

This section is enacted by way of proviso to sect. 18, and deals with the case exempted by sub-sect. 10.1 Hence the provisions of sect. 18 apply in all respects to applications under sect. 19 as if the words" correction or explanation" were omitted from the first subsection; only a real disclaimer with consequential corrections will be allowed. The section applies only to actions and petitions before judgment in the High Courts of Justice and in the Palantine Court of Lancaster.5

4

On the application for leave to amend the Court will go into the question of the proposed amendments in order to see if a primâ facie case has been made out for amending at all; it will not go into or decide on the admissibility of the proposed amendments, but leave that duty to the Comptroller and Law Officers. But the Court may go into the question of the proposed amendments and the merits of the case with a view to judge of what are the proper conditions to impose. The Court is not limited by the provisions of sect. 20 (post, p. 492) limiting the damages (unless the "original claim was framed in good faith and with reasonable skill and knowledge") to infringements after amendment, but may order that no damages shall be recovered nor injunction granted for acts committed before the disclaimer.9 Nor is the Law Officer so limited.10

8

Where a petition for revocation has been presented, and it is held that the patent is invalid, the order of the Court usually includes a stay of proceedings in order to give the applicant an opportunity of amending the specification, or appealing, before the patent is struck off the Register under sect. 20 (post, p. 492) and

1 Singer v. Stassen, 1 R. P. C. 123.

Lang's Patent, 7 R. P. C. 471 (8); Armstrong's Patent, 14 R. P. C. 754 (44).

3 Owen's Patent, 15 R. P. C. 760.

Cropper v. Smith, 1 R. P. C. 254; Lawrence v. Perry, 2 R. P. C. 180.

Winter v. Baybut, 1 R. P. C. 76.

Armstrong's Patent, 14 R. P. C. 755 (15). See also Re Hall, 5 R. P. C. 310 (25).
Dellwik's Patent, 13 R. P. C. 591.

* Per Webster, M.R., in Allison's Patent, 17 R. P. C. 516.

Lang v. Whitecross, &c., 7 R. P. C. 389.

10 Ludington, &c., Co. v. Baron, &c., per Rigby, L.J., 17 R. P. C. 217.

11 See Deeley v. Perkes, 13 R. P. C. 589; Armstrong's Patent, 14 R. P. C. 755.

Rule 60 (post, p. 538). at the Patent Office, an

Court must be left too.1

When the request for amendment is made official or verified copy of the order of the

The Terms usually imposed.

As the Court exercises a judicial discretion when leave is applied for, the Judge cannot be fettered by any rule or precedents as to the mode in which that discretion is exercised in any particular case;" and, unless the decision be clearly wrong the Court of Appeal will not interfere with it.3 "It requires a very strong case to show that the judges invested with that discretion have either exceeded the limits of the discretion given to them or have exercised it upon some principle which is inconsistent with the general law." 4

The exercise of the discretion of the Court does not interfere with the exercise of the discretion of the Law Officer under sect. 18 (7).

The general rule followed is that the terms imposed must allow of full compensation to those against whom leave to amend is asked, such as the payment of costs up to the time of leave being granted.5 Then again arises the question of allowing the amended specification to be sued upon in the action. In the absence of evidence of the applicant's knowledge of the invalidity of his patent and of such conduct as induced the defendants to set up an infringing trade, no condition has been imposed as to not taking an action on the amended claims. In cases of petitions for revocation the conditions are imposed as much in the interests of manufacturers generally as in those of the party presenting the petition.

Although not creating precedents, the following cases may be referred to as illustrating the application of the foregoing principles:—

Illustrations.

Where the applicants had patented "improvements in the construction of wire ropes," which consisted in laying the strands in the rope

by the same lay as the wires in the strand, and sought to amend

1 Rule 43, post, p. 536.

2 Allen v. Doulton, per Lord Esher, M.R., 4 R. P. C. 383.

3 Armstrong's Patent, 14 R. P. C. 747.

♦ Ludington, &c., Co. v. Baron, &c. (per Lord Halsbury, L.C.), 17 R. P. C. 748.
Gaulard v. Lindsay, 5 R. P. C. 192; Meyer v. Sherwood, 7 R. P. C. 283.

6 Codd v. Bratby, 1 R. P. C. 210.