India and Mauritius have tightened one of Asia's most closely watched tax treaties, adding a Principal Purpose Test that gives authorities a stronger tool to deny treaty benefits where an arrangement is found to have been structured primarily to obtain tax advantages. The amendment marks a significant shift in a pact long associated with cross-border investment flows into India, particularly through Mauritius-based vehicles.
The new safeguard is designed to address treaty shopping and other forms of abuse without dismantling the broader investment framework that has supported capital movement between the two jurisdictions for decades. Under the revised arrangement, tax benefits may be denied if one of the principal purposes of a transaction or structure is to secure those benefits in a manner inconsistent with the treaty's object and purpose.
Anti-Abuse Safeguard
The Principal Purpose Test, or PPT, has become a standard feature in modern tax treaty policy globally, especially after the OECD's Base Erosion and Profit Shifting initiative pushed countries toward stronger anti-avoidance rules. Its inclusion in the India-Mauritius treaty signals a further alignment with international tax norms and a clear intent to close pathways that could be used to route investments through Mauritius solely to gain preferential tax treatment.
For India, the amendment is a continuation of a broader effort to balance openness to foreign capital with tighter scrutiny of tax planning structures. The country has repeatedly moved to reduce opportunities for round-tripping and treaty abuse, particularly in agreements that historically offered low or zero capital gains tax advantages. By embedding the PPT at the treaty level, New Delhi gains a more direct basis to challenge arrangements that appear commercially thin but tax-driven.
The change is also likely to matter for multinational investors, private equity funds and holding companies that have used Mauritius as a jurisdiction for India-facing investments. While legitimate commercial structures are not the target, the new language raises the compliance bar and may require investors to demonstrate stronger business substance, governance and commercial rationale.
Grandfathering Remains Intact
A crucial feature of the amendment is the continued protection for investments made before April 1, 2017. Those legacy investments remain outside the scope of the Principal Purpose Test, preserving the grandfathering framework that has long been central to the treaty's transition away from earlier capital gains tax exemptions.
That carve-out is important because it limits immediate disruption for older structures that were established under the prior regime and have since been relied upon by investors in good faith. It also reduces the risk of retrospective uncertainty, a concern that often arises when tax treaties are tightened after years of liberal treatment.
Still, the grandfathering provision does not diminish the significance of the amendment. For new and future investments, the treaty now carries a more explicit anti-abuse standard that could influence structuring decisions, due diligence and dispute risk. Tax advisers are likely to place greater emphasis on substance, board control, operational presence and commercial purpose when evaluating Mauritius-linked investment routes into India.
Investment Climate Shift
The amendment reflects a broader policy evolution in India's international tax posture: preserve the country's attractiveness as an investment destination while ensuring that treaty benefits are not captured by structures lacking real economic purpose. That balance has become increasingly important as global tax authorities coordinate more closely on transparency, beneficial ownership and anti-avoidance standards.
For Mauritius, the revised treaty underscores the island nation's continuing role as a financial conduit, but under tighter rules. The jurisdiction remains relevant for India-bound capital, yet the era of relying on treaty arbitrage alone is clearly fading. Investors will now need to show that Mauritius is not merely a pass-through, but part of a genuine commercial or investment platform.
The practical effect of the amendment will depend on how the test is applied in assessments and disputes. Much will turn on administrative interpretation, evidentiary standards and the extent to which tax authorities can demonstrate that obtaining treaty benefits was a principal purpose of the arrangement. Even so, the direction is unmistakable: India and Mauritius are moving to harden the treaty against abuse while preserving continuity for older investments already protected by the grandfathering clause.