304 U.S. 364 (1938), 453, General Elec. Co. v. Wabash Appliance Corp.

Docket Nº:No. 453
Citation:304 U.S. 364, 58 S.Ct. 899, 82 L.Ed. 1402
Party Name:General Elec. Co. v. Wabash Appliance Corp.
Case Date:May 16, 1938
Court:United States Supreme Court

Page 364

304 U.S. 364 (1938)

58 S.Ct. 899, 82 L.Ed. 1402

General Elec. Co.


Wabash Appliance Corp.

No. 453

United States Supreme Court

May 16, 1938

Argued March 4, 7, 1938




1. Product claims 25-27, of Patent No. 1,410,499, to Pacz, for a filament for electric incandescent lamps or other devices, composed substantially of tungsten and made up mainly of a number of comparatively large grains of such size and contour as to prevent substantial sagging and offsetting during a normal or commercially useful life for such a lamp or other device, held void for want of a sufficiently definite disclosure. R.S. § 4888; 35 U.S.C. § 33. P. 368.

2. Claimed inventions, improvements, and discoveries, turning on points so refined as the granular structure of products, require precise descriptions of the new characteristic for which protection is sought. In a limited field, the variant must be clearly defined. P. 369.

3. A patentee may not broaden his product claims by describing the product in terms of function. P. 370.

4. A limited use of terms of effect or result, which accurately define the essential qualities of a product to one skilled in the art, may in some instances be permissible and even desirable, but a characteristic essential to novelty may not be distinguished from the old art solely by its tendency to remedy the problems in the art met by the patent. P. 371.

5. The difficulty of making adequate description may have some bearing on the sufficiency of the description attempted, but it cannot justify a claim describing nothing new except perhaps in functional terms. P. 372.

Page 365

6. A patentee who does not distinguish his product from what is old except by reference, express or constructive, to the process by which he produced it, cannot secure a monopoly on the product by whatever means produced. P. 373.

7. The product claims in question, which seek to monopolize the product, however created, may not be saved by a limitation to products made in accordance with the processes set out in the specification. P. 374.

91 F.2d 904 affirmed.

Certiorari, 302 U.S. 676, to review the reversal of a decree for injunction and accounting in a patent infringement suit.

REED, J., lead opinion

MR. JUSTICE REED, delivered the opinion of the Court.

Petitioner, General Electric Company, brought this patent infringement suit based on Pacz patent, No. 1,410,499, relating to a tungsten filament for incandescent lamps. The patent, issued March 21, 1922, on an application filed February 20, 1917, contains process and product claims; only the latter are here involved. The District Court for Eastern New York held claims 25, 26, and 27 valid and infringed, and gave petitioner a decree for an injunction and accounting. 17 F.Supp. 901. The Court of Appeals for the Second Circuit held that petitioner's product was anticipated by filament produced under the teachings of the Coolidge patent, No. 1,082,933, and reversed with directions to dismiss the bill of complaint. 91 F.2d 904. This decision conflicted with that handed down by the Circuit Court of Appeals for the Ninth Circuit, Anraku v. General Electric Co., 80 F.2d 958, which held

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the same claims valid and infringed. To resolve the conflict, this Court granted certiorari. .

In incandescent lamps, the tungsten filament, through which the electric current passes, grows more luminous than the carbon filament of the early days of the art. There were faults of "offsetting" and "sagging," however, affecting the efficiency of the first tungsten filaments. "Offsetting" occurs when, during heating in the use of the lamp, the filament forms crystals which extend their boundaries across the entire diameter of the filament, substantially perpendicular to its axis. The crystals in the filament thus come to have an appearance somewhat analogous to the joints in a bamboo rod. Lateral slipping of the crystals reduces the cross-sectional area at the point of contact of the crystals, with the result that the temperature at that point is increased, thus hastening the burnout, and the filament is weakened. "Sagging" is a change of position by the filament during incandescence. It elongates, and thus is forced out of the plane it occupied between fixed supports. Sagging has many objections. The sagging filament may touch the glass and end the life of the lamp. In gas-filled lamps, when sagging causes the coils to spread apart, the gas flows in between the coils and unduly cools the filament. Combatting sagging by additional supports is also said to cool the filament and reduce electrical efficiency.

[58 S.Ct. 901] Pacz undertook to remedy these faults. He carried out many experiments, and his 218th effort, made while he was in the employ of petitioner company, yielded the discovery disclosed by the patent in suit. The specification asserts that, by means of his invention,

the sagging is substantially eliminated, and "offsetting" of the filament is substantially prevented, during a normal or commercially useful life of the lamp.

He brings

into intimate

Page 367

association with tungsten a material [an alkaline silicate] which will have the desired influence upon the grain growth of the metal.

The specification continues as follows:

When the metal reaches the temperature at which extensive grain growth would ordinarily take place, the presence of this material intimately associated with the tungsten particles has a marked effect on the shape and size of the tungsten grains. The ingot of tungsten thus produced, whether it be due to the fact that the grains have not reached the equilibrium grain size or to other causes, is particularly susceptible to grain growth during subsequent heat treatments.

The probable reason why filaments made according to my invention do not sag is that the structure is comparatively coarse-grained. The coarse-grained filament produced by means of my invention does not "offset" so as to cut short the life of the lamp appreciably.

The District Court found that Pacz's patent exhibited novelty and invention; that Pacz produced large crystals early in the life of the lamp; that, although coarse-grained, and thus nonsagging, filaments meant "offsetting" to the art, where it was "common knowledge" that grains large enough to extend across the filament induced slippage, Pacz procured a particular kind of coarse-grained filament which did not "offset" because of the nature of the boundaries of the grains, their contour being "a very important element."

The Circuit Court of...

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