(A) Patents Act, 1970 - Sections 10, 48, 107A(b) - Indian Evidence Act, 1872 - Sections 45, 63-65, 114 - Standard Essential Patent (SEP) infringement - Doctrine of exhaustion - Quantum of damages - Suit patent claimed a decoding device; infringement litigation required proof of essentiality via claim-to-standard mapping and direct product-to-claim mapping - Expert reports submitted to prove essentiality lacked technical analysis and authors were not produced for cross-examination, rendering them inadmissible - In absence of claim charts or credible evidence, patentee failed to establish status of patent as an essential standard or to prove infringement - Patent holder sold components in open market; under provision concerning imported goods from lawful sources, patent rights were exhausted, precluding enforcement - Royalty rates for SEPs must be proven 'fair, reasonable, and non-discriminatory' (FRAND) with disclosure of comparable licensing agreements; unilateral assertion of royalty figures without supporting evidence of FRAND commitment is legally unsustainable (Paras 6, 11, 78, 110, 135, 155).

(B) Evidence - Best Evidence Rule - Adverse inference - Failure of a party to produce documentation such as essentiality analysis logs and licensing agreements, which are in their possession and form the basis of their claim, permits the court to draw an adverse inference under the law of evidence. (Paras 118, 119).

(C) Appeal - Scope and ambit - An appellate court must ensure that the impugned decision is not based on unproven assertions or procedurally infirm evidence and will set aside a decree where the plaintiff fails to discharge the burden of proving infringement and the essentiality of the invention. (Paras 170, 171).

Facts of the case:
An action for patent infringement was initiated against entities manufacturing hardware components that read digital encoded data. The patent in suit expired during the litigation, confining the dispute to the calculation of damages and the essentiality of the patent as a standard essential patent. The defendants argued that their components were purchased from authorized dealers in the open market, invoking the doctrine of international exhaustion, and that the patentee had failed to prove the essentiality of the patent or any actual infringement.

Findings of Court:
The court held that the patentee failed to establish that the patent was an essential standard, as the expert reports submitted were not properly proven and lacked mapping to the claims. Furthermore, the court determined that the patent holder's rights over the product were exhausted upon its sale in the open market, and no evidence was provided to demonstrate that the claimed royalty rates were fair, reasonable, and non-discriminatory.

Issues: The main issues were whether the patent in suit was an essential standard, whether the defendants' products infringed the patent claims, whether patent rights were exhausted by market sales, and whether the claim for damages met the requirement of FRAND licensing standards.

Ratio Decidendi: The court ruled that an infringement claim necessitates direct product-to-claim mapping, which was absent. Furthermore, legal principle dictates that once a patentee sells an item in the open market, patent rights are exhausted; therefore, no infringement could be claimed against users of those legitimate parts. The patentee holds the burden of proof to demonstrate the essentiality of the patent and the fairness of license fees, which the patentee failed to satisfy by withholding primary evidence.

Result: Appeals allowed.