The grey market premium (GMP) of the National Stock Exchange of India (NSE) IPO plunged 61.46% from its peak of ₹218 on 11 September to ₹84 by 2 pm on 19 September, according to online platforms that track unofficial grey market activity. The sharp correction has drawn attention ahead of the exchange's expected Dalal Street debut on 24 September.

The GMP Slide in Context

The GMP — an unofficial and unregulated indicator of the premium investors may be willing to pay over the IPO issue price before listing — had surged to ₹218 in the days following the issue's opening. By Friday afternoon, that figure had more than halved, settling at ₹84. It is important to note that the GMP carries no official standing and does not guarantee a stock will list at a premium. The metric is tracked by independent platforms, not regulated exchanges.

Notably, this is one of the most closely watched IPO listings in recent memory, given NSE's status as India's largest stock exchange by trading volume and its long-delayed market debut.

Subscription Status and Issue Details

Despite the GMP decline, the ₹22,569-crore IPO was fully subscribed by the second day of bidding. The issue received bids for 10,28,43,656 shares against an available 8,86,42,911 shares, according to data from the Bombay Stock Exchange (BSE). The subscription window closes on 21 September.

The price band has been fixed between ₹1,700 and ₹1,785 per equity share, implying a market capitalisation of up to ₹4.42 lakh crore at the upper end. The IPO is structured entirely as an offer for sale (OFS) of up to 12.64 crore equity shares by existing shareholders, which means no fresh capital will flow into the exchange from the share sale proceeds.

NSE's Financial Performance Raises Questions

The GMP correction may partly reflect investor scrutiny of NSE's recent financials. The exchange reported revenue from operations of ₹16,601.31 crore in FY26, down from ₹17,140.67 crore in FY25 — a year-on-year decline of more than 3%.

More significantly, revenue from transaction charges — one of NSE's primary income streams — fell to ₹13,057.01 crore in FY26 from ₹13,635.76 crore in FY25, a year-on-year drop of approximately 4%. Critics argue this revenue pressure could weigh on post-listing valuations, particularly given the premium at which the issue is priced.

What to Watch Before Listing

With the subscription period ending on 21 September and the listing set for 24 September, market participants will closely track any further movement in the GMP as well as broader equity market sentiment. A sustained grey market slide could dampen listing day expectations, though analysts caution that GMP movements in the final days before listing are historically volatile and not always predictive of listing performance.