coupler with means for yieldingly pressing the disk against the end of the pin fitting and means for limiting the movement of the disk in the direction of the pin fitting (which signifies merely some sort of shoulder at the orifice of the coupler to prevent the spring from forcing the disk out of the end of the bore).

Nothing is said in specification or claims concerning the release of the high pressure in the gun before uncoupling, but evidently this must be done if the movement of the perforated disk is to create a vacuum. The petitioner concedes that if the high pressure is maintained, the grease packed behind the washer will move forward with it and not only prevent the creation of a vacuum back of the washer but continue to exude from the coupler through the perforation in the washer. It is explained that the pressure may be released by a slight retraction of the plunger in the grease gun so as to permit the spring and washer to perform their function of creating a suction when the pin and coupler are disengaged.

Claims 1 to 6, inclusive, and 8 and 10, have been repeatedly held valid, but the invention has generally been limited to the novel means whereby upon the uncoupling of the gun from the pin fitting a suction is produced which removes excess lubricant from the point of contact of the two members. Although in the instant cases the validity of the claims is denied, we think they disclose novelty and invention to the extent indicated.

Claims 14 and 15 are of a different order. Claim 15 may be taken as typical. It is:

15. The combination with a grease cup comprising a tubular member having a closure seat, a closure, a pin extending through said tubular member and from both sides thereof, and a spring confined between said pin and closure, and tending to hold said closure on its seat, of a grease pump having a discharge conduit, and means co-acting with the ends of said pin for detachably connecting the discharge end of said conduit with said grease cup.

It will be noted that this claim describes a combination consisting of the pin fitting of Gullborg's patent, No. 1,307,733, with any grease pump having a bayonet type coupler. Nothing in the claim discloses the cup shaped reciprocating disk yieldingly pressed forward against the closure of the pin fitting. Grease guns having such a bayonet coupling were old in the art. The question is whether claims 14 and 15, unless restricted to the combination of a grease gun and coupler and a pin fitting such as are described in the specifications of the patent, are void as attempting to extend the monopoly of Gullborg's patent, No. 1,307,733, to exclude the use therewith of any grease gun except one having the suction device of the patent in suit.

With this background we pass to consideration of the specific cases presented.

No. 23

The petitioner, as owner of the Gullborg patent, filed a bill in the district court to restrain alleged infringement by the respondent. The latter did not sell pin fittings but did sell two types of grease pumps. The slotted coupler of the first has no slidably mounted cup-shaped perforated disk in its bore. Confessedly there is no means for producing the suction effect claimed for Gullborg's invention. The Circuit Court of Appeals, reversing the decision of the district court, held that in view of the limited scope of the invention disclosed in claims 1 to 6, inclusive, and 8 and 10, this device did not infringe. It further decided that as claims 14 and 15 must be limited to a combination embracing couplers embodying the suction effect, the only novel feature of the patent, or else be held void as attempting to gain protection for something not covered by the invention, this grease pump did not infringe those claims. The petitioner does not contest the holdings. The second gun sold by the respondent combines a receptacle containing grease under a pneumatic pressure of about one hundred pounds, the exit of which is connected to a pipe discharging into the chamber of a plunger-operated pump and a hose attached at the base of the pump chamber terminating in a copuling device like that of the Gullborg patent. The method of operation is that when the plunger is retracted beyond the orifice of the supply pipe grease is forced into the pump chamber by the air pressure in the receptacle. By the downward stroke of the plunger the entrance to the pumpchamber is closed and the grease therein forced into the hose and through the coupling and pin fitting to the bearing. By successive strokes a very high pressure can be built up in the hose. The Circuit Court of Appeals found, and we think correctly, that with this arrangement it was impossible to release the pressure in the grease line between the pump and the bearing before uncoupling the hose from the pin fitting, so as to permit the spring to force the disk forward in the bore of the coupler and create a suction as in Gullborg's patent; and that the accused device was subject to the very exudation of grease at the point of union which Gullborg's invention was intended to obviate. It therefore held that the accused grease gun lacked the only novel feature of the patented combination.

The decision went upon a question of fact. The petitioner offered no evidence to prove that the accused device operated to produce the suction effect claimed in the patent but relied upon the physical exhibits consisting of its own and the respondent's apparatus and upon ocular demonstrations of their operation. The respondent introduced evidence to show the absence of the suction effect in its

device and combatted the inference sought to be drawn from the physical operation of the two exhibits. We are satisfied that the Circuit Court of Appeals was correct in its decision that the accused device did not embody the novel feature claimed in the patent.

As respects claims 14 and 15, which are for a combination of the pin fitting covered by Gullborg's patent, No. 1,307,733, with a grease gun and coupler of any type, the Court of Appeals held that these must be read as claiming a combination of the patented pin fitting and a gun with the coupling device described in the specifications and having the suction effect set forth in the other claims or must be held void as unlawful attempts to extend the monopoly of the pin fitting which is described in Patent 1,307,733. The court sustained these claims by restricting their scope to conform to the other claims based on the suction effect and held they were not infringed by the respondent's apparatus. We do not understand the petitioner to seek a reversal of this holding. Its petition for certiorari and the assignments of error are bare of any attack upon this portion of the Circuit Court of Appeals' decision. These claims, however, are drawn in question in No. 31 and may more properly be discussed in that connection.

No. 31

In this case the respondent, as owner of the Gullborg patent, No. 1,307,734, sued the petitioners, who neither made nor sold pin fittings of the type covered by Gullborg's patent, No. 1,307,733, nor grease pumps or guns having the coupler construction of those described and claimed in the patent in suit. But the petitioners did sell pin fittings of a type with which a grease gun of the description of Gullborg's could be used, and grease guns having a bayonet slotted coupler, which could be used either with the pin fittings of Gullborg's patent, No. 1,307,733, or with others not covered thereby. These sales were charged to be contributory infringements of Patent No. 1,307,734. The district court so held and the Circuit Court of Appeals affirmed. What has been said with respect to claims 14 and 15 need not be repeated. The petitioners' grease guns are of on old unpatented type having couplers of a different construction from that disclosed in the patent. There is no assertion that they produce the suction effect of Gullborg's invention. The petitioners' pin fittings are not of the type described in Gullborg's patent, No. 1,307,733.

The proofs establish that the prior art embraced the use in combination of a grease gun composed of a chamber or pump, a hose, a hose-coupler, and a spring-closed fitting, the coupling being of the pin and slot or bayonet type. The respondent's position is, nevertheless, that if the petitioners furnish a gun, a part of this old unpatented and unpatentable combination, for use with the patented

pin fitting of Gullborg's, No. 1,307,733, they contributorily infringe claims 14 and 15 of the patent in suit because those claims describe the combination of any grease gun with the patented pin fittings. Again, the respondent says that as pin fittings made in accordance with the prior art, but susceptible of use with a gun covered by the patent in suit, were sold by petitioners, these sales constituted contributory infringements of all the claims of the patent.

[1] It is plain that Gullborg invented improvements of two of the mechanical elements of an old combination consisting of grease pump, hose, hose-coupler, and a grease cup or pin fitting. First, he contrived an improved pin fitting. This he patented as such (No. 1,307,733). Secondly, he invented an improved form of coupler to be attached to the end of the hose leading from the pump to the fitting. Instead of patenting this, as he did the pin fitting, he claimed a combination of pump, hose-coupler, and pin fitting, and embodied in the combination his improved form of coupler. (No. 1,307,734, the patent in suit; claims 1-6, 8 and 10.) He further claimed the combination between his patented pin fitting and any form of grease gun whether that claimed in his patent or unpatented and old in the art. (Claims 14 and 15.) The question then is whether, by this method, the patentee, by improving one element of an old combination whose construction and operation is otherwise unchanged, may, in effect, repatent the old combination by reclaiming it with the improved element substituted for the old element. That this cannot be done is shown by numerous cases in this and other Federal courts.*

Leeds & Catlin v. Victor Talking Machine Co., 213 U. S. 301, 325, 144 O. G. 1089, on which the respondent relies, is not in point. There the patent was a pioneer patent and the combination was of elements which were novel and neither of which possessed utility without the other. Each element was necessary to the operation of the other. The invention did not, as here, consist of the mere improvement of one element of an old combination.

[2] We are of the opinion that the owner of the patents cannot extend the monopoly of its patent for a pin fitting to preclude the use therewith of any grease gun not embodying the improvement in the coupling device evidenced by the patent in suit; and cannot extend the monopoly of the combination patent in suit

Edison Electric Light Co. v. Peninsular Light P. & H. Co., 101 Fed. 831; Heald v. Rice, 104 U. S. 737, 755; Underwood v. Gerber, 149 U. S. 224, 227, 229; Morgan Envelope Co. v. Albany Paper Co., 152 U. S. 425, 431, 432; Carbice Corporation v. American Patents Development Corporation, 283 U. S. 27, 31, 32; Wagner Typewriter Company v. Webster Co., 144 Fed. 405, 409; Langen v. Warren Axe & Tool Co., 184 Fed. 720; Harvey-Hubbell, Inc. v. General Electric Co., 267 Fed. 564; Troy Wagon Works Co. v. Ohio Trailer Co., 274 Fed. 612; General Electric Co. v. Ohio Brass Co., 277 Fed. 917; Radio Corporation v. Lord, 28 F. (2d) 257; Wall Pump & C. Co. v. Gardner Governor Co., 28 F.(2d) 334.

to prevent the use of a pin fitting which does not infringe the fitting patent, 1,307,733, with a gun having a coupler such as that claimed in the patent in suit.

In No. 23 the decree is affirmed. In No. 31 the decree is reversed and the cause remanded for further proceedings in conformity with this opinion.

So ordered.

The Chief Justice took no part in the consideration or decision of these cases.

DUPLATE CORPORATION AND PITTSBURGH PLATE GLASS COMPANY V. TRIPLEX SAFETY GLASS COMPANY OF NORTH AMERICA

Nos. 767 and 768. Decided May 18, 1936

470 O. G. 235; 298 U. S. 448

1. PATENTS-INFRINGEMENT

ACCOUNTING DEDUCTIONS.

Sale resulting in loss may not be offset by infringer against another independent sale resulting in gain for the purpose of extinguishing or reducing liability for profits.

2. SAME-SAME-SAME-SAME,

Extent of gain from sale is not susceptible of ascertainment without deduction and allowance of incidental costs; to make product of factory ready for market labor and material must be consumed by seller-manufacturer; cost of such consumption does not cease to be charge against proceeds because viewed in isolation it may be classified as waste; if waste is unavoidable or even fairly to be expected in normal course of such business there is diminution of profit for infringer as for others; in measuring gain from particular transaction defendant should have allowance for expense of incidental waste unless wastage is so great as to overpass bounds of reason.

3. SAME-SAME-SAME-SAME.

No allowance should be made of cost of glass sold by defendant and returned by customers for defects afterward discovered; the sales did not yield profit; they have no place in accounting at all.

4. SAME-SAME-SAME.

Defendant furnished glass to its subsidiary to make into infringing material. This was in addition to the regular business of defendant and is properly charged at cost of manufacture by defendant and not at market value. 5. SAME SAME-SAME DEDUCTIONS.

Reasonable royalty may not be deducted by defendant as compensation for economies effected through his own patented devices in manufacturing infringing products.

Sales of infringing product were sometimes at high price and sometimes at low price; owner of patent in holding infringers to accounting is not confined to all or nothing; there may be acceptance of transactions resulting in gain with rejection of transactions resulting in loss; patentee is not looked on as