Based on the provided legal document, here are the key points:

• The Supreme Court of India dismissed the appeal filed by the Delhi Development Authority against a decree granted to Durga Chand Kaushish, holding that the annual rent of Rs. 365/- for a 90-year lease could not be enhanced within the initial term. (!) (!)
• The plaintiff-respondent sued for a declaration that the rent, paid for a 90-year lease commencing April 1, 1931, could not be enhanced during the subsistence of the lease, and sought a refund of retrospectively demanded enhanced rent. (!)
• The defendants admitted that the lease was for a total period of 90 years but argued that the right to enhance rent under Covenants 9 and 10 operated within that period, claiming the lease was effectively for only 20 years initially subject to renewal and enhancement. (!) (!)
• The core legal dispute was whether the enhancement clause in the lease deed dated September 17, 1931, allowed rent enhancement before the expiry of the initial 90-year term or only upon the grant of a fresh lease after that term. (!)
• The lease deed explicitly stated the land was demised for a term of 90 years at a yearly rent of Rs. 365/-, with the first part of the deed containing the words of demise. (!)
• Covenant 9 stipulated that the lessor would execute a new lease for renewal "at the end of the term hereby granted," specifying durations for the first, second, and third renewals, with a proviso that the aggregate period of the original term and renewals should not exceed 90 years. (!) (!) (!) (!) (!)
• Covenant 10 provided that rent could be enhanced on the second renewal by up to 100% of the first renewal rate, and on the third renewal at the prevailing market rate. (!)
• The Supreme Court rejected the appellant's argument that the "original term" in the proviso included the renewal periods, noting that such an interpretation would render the explicit grant of 90 years and the condition of renewals "at the end of the term" absurd and inconsistent. (!) (!) (!)
• The Court applied the principle of ut res magis valeat quam pereat (that the thing may rather have effect than be destroyed), preferring an interpretation that gives effect to all clauses of the deed over one that renders them nugatory. (!)
• The Court held that where a grant is clear but an exception or proviso is ambiguous or uncertain, the clear grant prevails, and the ambiguous words creating the uncertainty should be disregarded. (!) (!)
• The Court refused to apply the feudal rule of construction that grants by the Sovereign should be construed strictly in favor of the grantor, stating that such a rule is inapplicable in a democratic republic where the State receives valuable consideration and has experienced draftsmen. (!) (!) (!) (!)
• The Court concluded that the only logical interpretation is that the lease is for 90 years at Rs. 365/-, with the right to renewal and enhanced rent accruing only after the expiry of that initial 90-year period. (!) (!) (!)
• The subsequent agreement of 1955 (Ex. P-4) and the conduct of the parties in accepting rent without enhancement were not relied upon to interpret the lease deed, as the decision was based solely on the language and terms of the 1931 deed itself. (!) (!)
• The appeal was dismissed, affirming the decision of the Division Bench of the Delhi High Court. (!) (!)