Universal application of Section 21 definition across statutory provisions

The definition and rule of commencement established under Section 21 of the Arbitration and Conciliation Act, 1996 apply universally across all provisions of the statute, including Section 9(2) and Section 43, unless a specific statutory exception is explicitly provided. The date on which the notice invoking arbitration is received by the opposite party serves as the sole benchmark for assessing compliance with statutory timelines, computing periods of limitation, and determining the legal validity of pre-arbitral interim protections. Courts cannot restrict the operation of Section 21 solely to limitation calculations under Section 43(2) of the Act. (Regenta Hotels Private Limited v. M/s Hotel Grand Centre Point | 2026 INSC 32)