-Kumar Salva Raghuvanshi

Introduction.

• Unlike U.S Patent Law, Indian law does not address the issue of infringement directly.

• Patent Act, 1970 does not define how to determine whether a patent has been infringed or not.

• Dicta of court’s are only guiding principles.• Vidya Prakash v Shah Charan Singh: Lahore H.C

considered Novelty, Utility and description as the basis for determining infringement.

1. Literal Infringement

• A patent is infringed if the accused product or process includes every element exactly as recited in at least on of its claim.

• Every word of a claim is used in a product, infringement is said to be literal.

• Thus, claims must be drafted and prosecuted with great care to minimise the possibility of competitors who will literally infringe.

1.1 Markman v. Westview Instruments No. 95-26, 64 USLW 4263 (1996) [SC]

Facts: Markman combined computer and bar code technology to minimise

lost garments and employee theft during the dry cleaning process. The system developed was capable of monitoring and reporting the

status, location and movement of clothing in dry cleaning establishment.

The claimed invention allowed the detection of spurious additions to the inventory as well as deletions therefrom.

Defendant system was capable of tracking invoice numbers, total prices and receivables. {It did not track clothing}

Issue: Whether inventory means clothing and/or totals?

Markman cont…

• Argument of Markman: Inventory included clothing and/or totals.

• Argument of Defendant: Inventory meant clothing.Jury: Defendant infringed Markman patent.Trial Court: Not an infringement, because inventory

referred exclusively to articles of clothing and accused device merely maintained a listing of invoices, it could not track the location of individual garments as they moved about the shop and therefore could not infringe.

Markman cont…Federal Circuit: (on appeal) affirmed the decision of

trial court. The court established two categories of evidentiary inputs for use in claim interpretation.

I. Intrinsic Evidence: consist of claims, the specification and prosecution history. Court were required to consider all intrinsic evidences to determine meaning of claims.

II. Extrinsic Evidence: Dictionaries and expert tetimony.Supreme Court: Affirmed the decision of federal court.

2. Doctrine of Pith and Marrow (U.K)

• To constitute infringement, the article must take each and every one of the essential integers of the claim. This constitutes pith and marrow principle of infringement.

• Directed against colourable evasion of patent claim.• Patent owner has remedy against an alleged infringer who

does not take the letter of the invention but nevertheless appropriates its substance or “pith and marrow”.

• Thus, person who borrows the substance of the patented invention cannot escape the consequences of infringement by making immaterial variations.

2.1 Catnic Components v. Hill & Smith [1928] R.P.C. 183 H.L.

Facts:Claim of the patent was for lintel which was used to

provide structural support over a door or window opening in a brick wall, the structure of the lintel was such that the upper plate of the same was supported lower plate by two rigid supports, one in front and other extending vertically from the one plate to the other at the rear. Defendant lintel had a rear support which was inclined 6 degrees or 8 degrees from the vertical. The defendant argued that his lintel would have to be exactly vertical to infringe.

Catnic Components v. Hill & Smith cont…

Trial Court: held there was an infringement under the "pith and marrow" doctrine.The Court of Appeal: Overturned the ruling and held that the "vertical" requirement was an exact and essential element of the patent. The House of Lords: Reversed the decision of the Court of Appeal, finding that there was an infringement, and affirmed the use of purposive construction in patent interpretation.

Catnic Components v. Hill & Smith cont…

The House of lords laid 3-Step test:1. Does the variant have a material effect upon the way the invention

works? If yes, the variant is outside the patent claim. If no, the next question comes.

2. Would the fact that the variant had not material effect have been obvious at the date of publication of the patent to reader skilled in the art. If no, variant is outside the claim. If yes, the third question needs to be asked.

3. Would the reader skilled in the art nevertheless have understood from the language of the claim that the patentee intended that strict compliance with the primary meaning was an essential requirement of the invention. If yes, the variant is outside the claim. If no, there is infringement.

2.2 Improver Corp. v. Remington Consumer Products Ltd. [1990] F.S.R 181

Facts:The patent covered a depilatory device having a helical spring driven by motor. The spring when rotated gripped hairs between its coil and plucked them from the skin. The alleged infringement replaced the spring with a rubber rod having slits at the surface.Issue: Whether the slit rubber rod was a helical spring?

Article-69, EPCExtent of Protection:

(1) The extent of the protection conferred by a European patent or a European patent application shall be determined by the claims. Nevertheless, the description and drawings shall be used to interpret the claims. (2) For the period up to grant of the European patent, the extent of the protection conferred by the European patent application shall be determined by the claims contained in the application as published. However, the European patent as granted or as amended in opposition, limitation or revocation proceedings shall determine retroactively the protection conferred by the application, in so far as such protection is not thereby extended.

Protocol on Article-69, EPC"Article 69 should not be interpreted in the sense that the extent of the protection conferred by a European patent is to be understood as that defined by the strict, literal meaning of the wording used in the claims, the description and drawings being employed only for the purpose of resolving an ambiguity found in the claims. Neither should it be interpreted in the sense that the claims serve only as a guideline and that the actual protection conferred may extend to what, from a consideration of the description and drawings by a person skilled in the art, the patentee has contemplated. On the contrary, it is to be interpreted as defining a position between these extremes which combines a fair protection for the patentee with a reasonable degree of certainty for third parties."

Improver Corp. v. Remington cont…

Court:The court held that if the issue was whether a feature embodied in an alleged infringement which fell outside the primary, literal or a contextual meaning of a descriptive word or phrase in the claim was nevertheless within the language as properly interpreted , the court should ask itself the following three questions:1. Does the variant have a material effect upon the way the invention works? If yes,

the variant is outside the patent claim. If no, the next question comes.2. Would the fact that the variant had not material effect have been obvious at the

date of publication of the patent to reader skilled in the art? If no, variant is outside the claim. If yes, the third question needs to be asked.

3. Would the reader skilled in the art nevertheless have understood from the language of the claim that the patentee intended that strict compliance with the primary meaning was an essential requirement of the invention. If yes, the variant is outside the claim. If no, there is infringement.

Improver Corp. v. Remington cont…

Held:Applying the three step test, the court held that to a PHOSITA reading the claim it would show that the patentee intended strict compliance with the component helical spring in its primary meaning and not in a wide generic sense, as an essential feature of the invention. On this basis court held that rubber rod fell outside the meaning of helical spring and did not infringe.

3. Doctrine of Equivalents (U.S.)

• In the absence of literal infringement, a product may nevertheless be found to infringe a patented product if it is found to be its substantial equivalent.

• Under this doctrine, an accused device infringes a claim if it “performs substantially the same function in substantially the same way to obtain the same result”.

• First applied in the case of Winans v. Denmead.

3.1 Graver Tank & Mfg. v. Linda Air Products Co. 339 US 605 (1950)

Facts: Plaintiff obtained an improvement patent on an electric welding

composition or flux with specifications that were basically a combination of alkaline earth metal silicate and calcium fluoride. Defendant began to produce its own composition that instead used silicates of manganese, not an alkaline earth metal, for the silicates of magnesium, which is an alkaline earth metal used by Plaintiff. Plaintiff charged Defendant with infringement. Plaintiff had mentioned manganese in its specifications, but it was not within the specific claims of the patent.

The chemist had testified that magnesium and manganese were equivalent in the wielding art, and the trial court had properly found that Lincolnweld and Unionmelt fluxes were in all respects equivalent.

The United States district court found infringement, and the Court of Appeals affirmed the infringement claim.

Graver Tank & Mfg. v. Linda Air Products cont…

Court Stated:1. Unimportant and insubstantial changes and substitution in the

patent will amount infringement.2. As regards what would constitute equivalents, the court stated

that when the accused product or process performed substantially the same way to obtain the same result (triple identity test or function-way-result), an infringement had occurred under the DOE.

3. Interchangeability of the claimed and substituted ingredients was an important factor in an equivalency determination. It has to be proved with views of experts, learned texts and the disclosure in the prior art.

3.2 Warner-Jenkinson v. Hilton Davis (516 US 1996)

Facts: The plaintiff Hilton Davis Chemical Co., a dye maker, had developed an

"ultrafiltration" process to purify dyes. An amendment to the patent had specified that a solution used in the process must have a pH level between 6.0 and 9.0. The amendment was filed in order to clarify that this patent did not overlap with a previously patented process (Booth Patent) that used a solution with a pH level above 9.0 - however, the plaintiff was unable to explain why the amendment stated a lower level of 6.0. The defendant had developed a process using a solution with a pH level of 5.0, which was outside the range of the plaintiff's patent.

The plaintiff sued for infringement, conceding that the defendant's process did not literally infringe, but relying on the doctrine of equivalents to support the claim of infringement. The defendant argued that the doctrine of equivalents was no longer appropriate for courts to use because Congress had made some changes to the patent statute after the Supreme Court's 1950 decision establishing the propriety of using the doctrine.

Warner-Jenkinson v. Hilton Davis cont….

Issue: Whether the Patent Act, 1952 overruled the Doctrine of Equivalent?District Court: No infringement.Court of Appeal: Affirmed.

“Certiorari was granted”

Warner-Jenkinson v. Hilton Davis cont….

Supreme Court (Reasoning):• Insubstantial difference infringement.• Restriction of DOE to variants described in

specifications Rejected (PHOSITA).• Intention of infringer not relevant.• Function-way-result Test not only test.• Prosecution History Flexible & Rebuttable

bar.

Warner-Jenkinson v. Hilton Davis cont….

Supreme Court Held:1. DOE is not inconsistent with Patent Act.2. DOE must be applied to individual element of patent claim, not to invention as

whole.3. Prosecution history estoppel does not apply in every instance where the

patent claim has been amended during application process, regardless of reasons for change.

4. Patentee’s addition of lower pH during application process did necessarily preclude application of DOE as to that element.

5. Remand was required to determine whether reason for amending patent claim to add lower pH limit was sufficient to avoid prosecution history estoppel.

6. DOE does not require proof of intent.7. DOE is not limited to equivalent disclosed within patent itself.

3.3 Festo Corp. Shoketsu Kinzoku Kogyo Kabushiki Co. Ltd, 535 U.S. 722

Background History:It is a United States Supreme Court decision in the area of patent law that examined the relationship between the doctrine of equivalents and the doctrine of prosecution history estoppel (which holds that a party who makes a change to a patent application to accommodate the requirements of patent law cannot claim indirect infringement of an element that was narrowed by that change).

Festo Corp. Shoketsu Kinzoku cont…

Facts:Festo Corporation owns two patents for an improved magnetic rod less cylinder, a piston-driven device that relies on magnets to move objects in a conveying system. When the patent examiner rejected the initial application for the first patent because of defects in description, the application was amended to add the new limitations that the device would contain a pair of one-way sealing rings and that its outer sleeve would be made of a magnetisable material. The second patent was also amended during a re-examination proceeding to add the sealing rings limitation. After Festo began selling its device, SMC entered the market with a similar device that uses one two-way sealing ring and a non-magnetizable sleeve. Festo filed suit, claiming that SMC's device is so similar that it infringes Festo's patents under the doctrine of equivalents.

Issue: Does a patentee, by narrowing a claim to obtain a patent, surrender all equivalents to the amended claim element?

Festo Corp. Shoketsu Kinzoku cont…

District Court:Rejecting SMC's argument that the prosecution history, or the public record of the patent proceedings, estopped Festo from saying that SMC's device was similar, the District Court ruled in Festo's favour. Court of Appeal:Ultimately, the en banc Court of Appeals held that the prosecution history estoppel applied, ruling that estoppel arises from any amendment that narrows a claim to comply with the Patent Act. The Court of Appeals also held that, when estoppel applies, it bars any claim of equivalence for the element that was amended.

“Certiorari was granted”

Festo Corp. Shoketsu Kinzoku cont…

Supreme Court:1. The Court held that prosecution history estoppel may apply to any claim

amendment made to satisfy the Patent Act's requirements, not just to amendments made to avoid the prior art, but that estoppel need not bar suit against every equivalent to the amended claim element.

2. Noting that by amending an application the inventor is deemed to concede that the patent does not extend as far as the original claim,

3. The Court reasoned that the patentee should bear the burden of showing that the amendment does not surrender the equivalent in question.

4. Justice Kennedy wrote that, in cases where an equivalent was unforeseeable at the time of the application, the patentee could rebut the presumption that prosecution history estoppel barred a finding of equivalence by showing that at the time of the amendment one skilled in the art could not reasonably be expected to have drafted a claim that would have literally encompassed the alleged equivalent.