Mumbai: India’s central bank on Wednesday implemented a new definition for systemically important non-banking financial companies, called upper-layer NBFCs, bringing such companies with assets exceeding ₹1 lakh crore under the umbrella that requires a public listing of shares, in a move that appears to have all but shut the door for the parent of the country’s largest business group to remain privately held.In doing so, it rejected feedback from the industry that suggested raising the cap to ₹2.5 lakh crore. It also said those falling in the category would be “specifically identified annually” by the regulator, a condition it first spelt out with the original scale-based regulations released in 2002. In FY26, however, the regulator did not publish a list of upper-layer NBFCs.What RBI saysThis particular circular, one among hundreds of technical circulars published by the central bank, assumes importance due to the singular question surrounding upper-layer NBFC regulations—whether Tata group parent Tata Sons will be mandated to do a public listing. Wednesday’s circular finalised a regulatory threshold the Reserve Bank of India (RBI) first floated in a draft circular in April. Previously, inclusion as an upper-layer NBFC hinged on whether or not a company ranked in top 10 by asset size in the country.Also Read: Tata Sons' chairman N Chandrasekaran declines pay hike amid group concernsTata Sons, the unlisted holding company of the sprawling salt-to-semiconductors conglomerate, was mandated to list by the original September 2025 deadline. In January last year, when RBI last published the list of upper-layer NBFCs expected to list, it said Tata Sons’ application to surrender its NBFC licence was under consideration. Since then, the regulator has remained conspicuously silent on the matter.Tata Sons’ majority owner Tata Trusts has passed a resolution saying the company should remain unlisted. Two of its vice chairmen—Venu Srinivasan and Vijay Singh—have subsequently said in public statements that a listing would be a positive outcome. Their comments have become a source of discord among trustees, including Trusts chairman Noel Tata, who has firmly opposed a listing.A public listing of Tata Sons has far-reaching implications because of how its shareholders wield control on its board. The majority owner, the public charitable trusts under the Tata Trusts umbrella, has special rights because its structure as a private limited company allows such privileges, which would cease if the company is converted into a public limited structure, a necessity ahead of a public listing.Important decisions currently require an affirmative vote by the nominee directors of Tata Trusts, whereas in a public company, all board members would have an equal vote, removing the main lever of control the trusts wield.The new norms will apply from the date RBI issues a fresh list of companies that would fall in the upper layer category.“The upper layer shall consist of NBFCs having asset size of Rs 1 lakh crore and above as per the latest audited balance sheet for the financial year,” RBI said. “The upper layer shall comprise of those NBFCs which are specifically identified annually by the Reserve Bank as warranting enhanced regulatory requirement based on the criteria...”In final guidelines published on the methodology for identifying NBFC–UL entities, the central bank simplified the earlier multi-parameter approach and rejected suggestions to raise the asset threshold to Rs 2.5 lakh crore.Tata Sons' Asset BaseTata Sons’ standalone asset size is about Rs 1.9 lakh crore, showed an ETIG analysis. The Tata conglomerate has a consolidated market capitalisation of more than $300 billion.Highly placed group officials close to the development said the regulatory tweaks appear to keep open the possibility of a future Tata Sons listing, although the implications would need to be studied closely.Tata Sons did not comment on ET’s queries on the subject till publication of this report.Also Read: Noel Tata flags unresolved issues; Tata Sons chairman reappointment on holdRBI said it had received feedback seeking to raise the threshold to at least Rs 2.5 lakh crore, along with additional metrics such as profitability and asset quality. However, it rejected the proposal, saying the ₹1 lakh crore threshold was determined based on the current profile of the sector and analysis of existing upper-layer NBFCs.Feedback submitted to RBI argued that asset size alone may not fully capture systemic importance and should be supplemented with parameters reflecting interconnectedness and systemic risk. It also said any revised methodology should account for an entity’s risk profile, leverage, interconnectedness and other supervisory considerations.The regulator also moved to make the framework more transparent by replacing the earlier parametric scoring methodology with a clear asset size criterion, which it said is a reasonably good proxy for systemic significance.Separately, RBI said listing will not be mandatory for government-owned NBFCs that are fully owned and controlled by the state, given their developmental mandate.