Early Life and Education

Arvind P. Datar began his academic journey in Pune. He completed his B.Sc. (Hons.) in Physics and Mathematics, before turning to law. He studied law at Dr. Ambedkar Government Law College, Chennai. In addition, he is a qualified Cost & Works Accountant (ICWA) — a qualification that enriches his command over tax, corporate, and accounting law issues.

Early Legal Career

Mr. Datar started his legal career in 1980, initially working in the chambers of Mr. N. Natarajan and Mrs. Ramani Natarajan. He later joined the firm of Subbaraya Aiyer, Padmanabhan & Ramamani (from about 1981 to 1984), where he practiced in income tax, central excise, customs, and company law matters. On 1 March 1984, he established his independent practice at the Madras High Court, appearing on the original side, appellate side, and writ jurisdiction. Over time, he expanded his practice to the Supreme Court and multiple high courts, taking up constitutional, regulatory, tax, and corporate litigation.

Designation as Senior Advocate & Practice Expansion

Mr. Datar was designated as a Senior Advocate by the Madras High Court on 18 July 2000. Mr. Datar has been regularly appearing before the Supreme Court of India on constitutional, tax, corporate, commercial, and regulatory law matters. He has also served as Amicus Curiae in various Supreme Court and High Court matters, particularly in constitutional and tax law disputes.

Major Cases and Legal Highlights

Over his distinguished career, Mr. Datar has been involved in a number of high-stakes and legally significant matters:

  • He represented Cairn Energy plc in a Bilateral Investment Treaty arbitration in The Hague against the Government of India, challenging the retrospective tax regime.

  • He has appeared in landmark constitutional jurisprudence, including S. Puttaswamy v. Union of India (right to privacy case), which affirmed privacy as a fundamental right under the Indian Constitution.

  • In Abhiram Singh v. C.D. Commachen, he argued before a larger bench of the Supreme Court on the electoral law question whether referencing religion in election campaigns is a corrupt practice.

  • Mr. Datar has handled taxation and revenue law battles, excise, customs, and corporate regulatory litigation across different high courts and tribunals.

Institutional Roles, Writing & Thought Leadership

Apart from litigation, Mr. Datar is a scholar and legal institution builder:

He is Editor-in-Chief of Ramaiya’s Guide to the Companies Act, and General Editor of Essays and Reminiscences: A Festschrift in Honour of Nani A. Palkhivala. He has authored (or coauthored) works such as Guide to Central Excise: Law and Practice, Guide to Central Excise Procedure, Commentary on the Constitution of India, and the biography Nani Palkhivala: The Courtroom Genius. He has published over 300 articles in journals, periodicals, and newspapers.

He is a Trustee of the Palkhivala Foundation, Director of the Nani Palkhivala Arbitration Centre, Chairman of Maharashtra Building Trust, and Vice President of the Bar Association of India. He also served as Joint Secretary of the Tamil Nadu Mediation & Conciliation Centre.

As visiting faculty, he has lectured at the National Judicial Academy, Bhopal, Tamil Nadu State Judicial Academy, and institutions such as Cambridge University (2003) and University of Cape Town (2004).

Honours, Recognition & Awards

In 2025, Mr. Datar received the inaugural Fali Nariman Memorial Award, in recognition of his contributions to constitutional, commercial, and taxation law. His career is frequently cited as one that combines rigorous scholarship with high-stakes advocacy, and many peers in the bar regard him as a model of integrity and intellectual depth.

Legacy and Influence

Over four decades of practice, Arvind P. Datar has made lasting contributions to Indian legal jurisprudence, particularly in tax, constitutional, and regulatory law. He is admired not just for his courtroom success, but for his scholarly writings, institutional leadership, and mentorship of younger lawyers. His presence in cases spanning from domestic constitutional litigation to international arbitrations positions him as one of India’s pre-eminent senior advocates in his domain.