Mumbai: The BSE IPO index, a measure that tracks recent mainboard listings, surged 35% in the first five months of FY27, its strongest April-August performance in three years, to an all-time high on Monday, boosted by strong openings by a clutch of recent stock market debutants. The BSE SME IPO index jumped 55%, marking its best showing for the period in two years. The benchmark is 5% away from its record levels.

The gains far outpaced the broader market. The Sensex and Nifty rose 6% each during April-August, while the BSE MidCap 150 gained 19% and the BSE SmallCap 250 climbed 29%.

But the strong performance of the IPO indices masks a highly concentrated rally, with 15 stocks accounting for nearly 80% of the gains in the BSE's 73-stock IPO index. For BSE's 105-stock SME IPO index, 24 stocks contributed to about 89% of the rise in the benchmark

The indices are designed to track relatively recent listings. A stock market debutant enters the BSE IPO index on the third day after listing and is generally removed after completing one year. In the case of the SME IPO index, a stock is included on the second day of listing and moves out after a year. An SME stock exits earlier if it migrates to the BSE Mainboard. Both indices are rebalanced monthly.

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"Retail and HNI investors are opting for fresh growth stories over legacy large-cap names that carry FPI overhang, valuation baggage, and uncertain earnings visibility," said Rajesh Singla, CEO and fund manager at Alpha AMC & Planify.

Of the 4661 points gained by the BSE IPO index between April and August, Meesho, Lenskart Solutions, Tata Capital, Billionbrains Garage Ventures, Rubicon Research, LG Electronics India, Physicswallah, Urban Company, Shadowfax Technologies, Sudeep Pharma, ICICI Prudential Assets, Aequs, Emmvee Photovoltaic Power, Fujiyama Power Systems and Clean Max Enviiro Energy Solutions together contributed 3,738 points.

Of the 105 stocks in the BSE SME IPO index, 24 companies, including Zelio E Mobility, Indo SMC, Airfloa Rail Tech, Exato Tech, SK Minerals & Additives, LT Elevator, Aptus Pharma and Purple Wave Infocom, contributed 34,472 points to the index's 38,772-point rise, accounting for nearly 89% of the gains.

The remaining 56 gainers added 6,520 points, while 25 stocks dragged the index down by 2,220 points.