What is the 10 rs stamp paper validity ?

A document written on Rs.10 stamp paper in Delhi is not automatically void but will be inadmissible and cannot be acted upon if the proper stamp duty exceeds Rs.10; the Indian Stamp Act requires instruments to be duly stamped and permits impounding until duty and penalty are paid (Sections 33, 35 and related provisions). [https://legislative.gov.in/sites/default/files/A1899-2.pdf]. The Supreme Court has held that non'stamping is a curable defect (an instrument is inadmissible until duty+penalty are paid) -see Hindustan Steel Ltd. v. Dilip Construction Co., (1969) 1 SCC 597. [https://www.courtkutchehry.com/Judgement/Search/t/270534-hindustan-steel-ltd-vs-ms] and the seven'judge Constitution Bench decision In Re: Interplay between Arbitration Agreements -(Curative Petition) (Dec. 13, 2023) (which confirmed that insufficient stamping renders an instrument inadmissible but not void and can be cured by paying duty/penalty). [https://www.latestlaws.com/latest-caselaw/2023/december/2023-latest-caselaw-922-sc]. Remedy: have the deficit stamp duty and prescribed penalty paid and the instrument endorsed/regularised by the Collector or under court direction (Sections 35/36/38/40 procedure in the Stamp Act). [https://legislative.gov.in/sites/default/files/A1899-2.pdf]. For rent agreements in Delhi a Rs.10 stamp is generally insufficient; Delhi uses e'stamping and small'tenancy/11'month agreements ordinarily attract a nominal duty (commonly cited as about Rs.50) whereas longer leases attract 2%'5% of annual/average rent as applicable, so use e'stamp of the correct value (SHCIL e'stamping) or pay the correct duty and register if tenancy exceeds 11 months. [https://delhi-lawyers.in/rent-agreement] [https://www.shcilestamp.com].