New Delhi, Jan. 21 -- The Supreme Court's ruling in the Tiger Global-Flipkart stake-sale case has been framed as a blow against tax-treaty abuse. In reality, it does something far more consequential: it rewrites the operating assumptions under which foreign capital has been invested in India for decades.

While the judgement is fact-specific, its reasoning dismantles the comfort investors drew from treaty residency, grandfathering assurances and carefully structured exits. It resets India's investment jurisprudence, with ramifications for private equity (PE), venture capital (VC), foreign portfolio investors (FPIs) and long-term strategic capital.

The most immediate consequence of the ruling is for pre-2017-18 PE, VC and foreign direct i...