Rs 30,000 cr loss in 3 months: Why BSE stock is failing investors and should you buy now?

BSE Ltd, one of the biggest stock market winners of the last two years, is now testing investor patience after losing nearly Rs 30,000 crore in market value over the past three months. The stock has come under pressure as three worries hit the exchange business at the same time: the new Closing Auction Session, weaker index options volumes and tighter bank guarantee rules for brokers. The concerns have forced brokerages to cut earnings estimates and lower their view on the stock.

Analysts say risks are compounding for BSE because domestic proprietary traders, who form a large part of equity options turnover, are facing pressure from the securities transaction tax hike, RBI’s bank guarantee norms and CAS.

Why BSE is failing investors?

The main problem, according to analysts, is the market had priced the stock for strong and sustained growth in Sensex options. That assumption is now being questioned.


BSE’s options average daily turnover for August month-to-date was down 12% compared with July, according to Jefferies. The brokerage also said options average daily turnover for NSE and BSE fell 14% and 12%, respectively, from July levels. In the second week of CAS, options turnover was down 20-23% for BSE and NSE compared with the first week.

Nuvama’s numbers show a similar stress. It said BSE’s average daily premium turnover fell to Rs 181 billion, down 22.7% week-on-week, the lowest level since January 2025. More importantly, the fall was led by contracts, which declined 30.5% from 150 million to 104 million compared with July.

CAS is the biggest immediate trigger. The new closing auction mechanism is meant to improve closing price discovery and reduce manipulation. Sebi has said the system is here to stay. But the rollout has changed the way traders behave on expiry day.

Also Read: Rs 91,685 crore gone! 88% retail investors lost money in F&O trading in FY26 even after strict Sebi rules

Earlier, option premiums would decay in a more predictable manner into expiry. That allowed many short-duration traders to repeatedly enter and exit positions. Nuvama said CAS has introduced uncertainty in final settlement because the closing price is now discovered through an auction. This has weakened theta-harvesting strategies, reduced leverage for buyers and reduced seller interest because option decay has become less predictable.

That hurts BSE more because its derivatives business is heavily dependent on expiry-day volumes. Nuvama said BSE expiry-day contracts fell 33.2%, compared with a 23.6% decline on non-expiry days. Expiry day formed 72.6% of BSE’s contracts in July, making the exchange more exposed to any change in expiry-day trading behaviour.

Jefferies also flagged BSE’s dependence on Sensex weekly options. The brokerage said BSE’s market share gains have been led largely by expiry day, while gains outside T-0 and T-1 days have slowed. It also said BSE’s expiry-day market share is now similar to NSE, limiting further easy gains.

This is where investor concern deepens. BSE’s past rally was built on the idea that it could keep gaining share in the index options market. If that growth slows, the stock’s valuation becomes harder to defend.

Jefferies said consensus was factoring Rs 27,000 crore of options average daily turnover in FY27 and around 20% growth in later years. But it pointed out that BSE’s average daily turnover has been below Rs 270 billion for the last three months. It cut FY27-FY29 earnings per share estimates by 5-12%.

Nuvama has cut its FY27 and FY28 EPS estimates by 6.3% and 15%, respectively. It now models remaining FY27 average daily premium turnover at about Rs 186 billion, with blended FY27 turnover at Rs 219 billion, down from Rs 241 billion earlier.

The second pressure point is RBI’s bank guarantee norms. These rules may raise capital requirements for brokers and reduce turnover efficiency for high-frequency strategies. Nuvama said the impact may be gradual but could cap recovery into FY28. Jefferies said the rules may not hit immediately but could reduce premium turnover by up to 10% over the next year.

What are the avenues for turnaround?

Jefferies said BSE could raise option fees, which may add 6-7% to EPS, or increase messaging fees for its co-location facility, which may add 8% to profit after tax. But it also said investors may be assigning a higher valuation to volume-led growth, not fee hikes.

The stock is not without support. More than half of the 18 analysts tracking BSE still have buy ratings, and the 12-month consensus target implies about 20% upside. A recovery in volatility, faster adaptation to CAS or deeper auction liquidity could help volumes recover.

However, Jefferies has recently downgraded BSE to Underperform and cut its price target by 16% to Rs 2,940 from Rs 3,520. Nuvama has also downgraded BSE to Hold and cut its target price to Rs 3,240 from Rs 4,090.

(Disclaimer: Recommendations, suggestions, views and opinions given by the experts are their own. These do not represent the views of Economic Times)