New Delhi: Mukesh Ambani-led Reliance Industries may lose its stock market bellwether position as the share performance has been poor for a long time, experts warned.

Reliance Industries, the country's most respected company and the biggest private sector entity in terms of profits and revenue, has been a sort of benchmark for Indian market for many years by virtue of its large shareholding and valuation.

The stock enjoys the maximum weightage in the Sensex and a rise or fall of one percent in its share price can lead to a surge or plunge of nearly 20 points in the benchmark index.

RIL shares have tumbledby nearly 7.5 percent over the past one year, even as the Sensex has gained about 1,259 points or 7.5 percent over the same period.

Experts suggest that the gain in the Sensex would have been higher by at least 300-400 points if the RIL shares had performed in-line with the broader market, if not any better.

Less than half of the 30 Sensex stocks have registered a fall over the past one year and the likes of BHEL, DLF, NTPC and Reliance Communications have seen a fall even greater than that of RIL.

However, RIL has the maximum weightage of over 11 percent in Sensex, while other losers are among very low-weight stocks in computation of Sensex movements.

"RIL is no longer the market mover. The biggest reason is the uncertainty in the stock on concerns of gas output from KG-D6 basin. Investors are not passionately following the stock at present," CNI Research CMD Kishore P Ostwal said.

Geojit BNP Paribas Financial Services' Research Head Alex Mathews also said that the co-relation between Sensex and RIL has gradually come down over the years.

"Some of the key reasons are that exposure has been shifted to other blue-chip companies, mainly banking sector. Also, exposure of fund mangers has gone down in the oil & gas sector," he added.

Expressing similar sentiments, Ashika Stock Broking' Research Head Paras Bothra said that the mindset has changed from earlier days when Reliance used to lead the market.

"This is obvious from the fact that the index has moved up despite the fact that RIL was trading in the negative," he said, adding that some other companies like ONGC, Coal India, ICICI, Infosys and Larsen and Toubro had now started to move the market indices.

Unicon Financial's CEO Gajendra Nagpal said that there were multiple challenges around the RIL stock, because of which it has underperformed. "There was a time when Infosys used to dictate terms and then RIL started to take the lead... these things keep changing. At present the scenario is such that no single stock is dictating the market rather it is a composition of stocks which are leading the index," Nagpal said.

He, however, added that RIL could come back to its glorious days, provided that margin pressures in its various businesses like refinery and polyester were taken care of.

Geojit BNP Paribas' Mathews also said that RIL could become a market mover again in the future and its under-performance might not continue for long.

"In the long-term, the company has the potential to bounce back as the market leader. Oil prices may double in the next 3-years, so it is likely that valuation of RIL will also increase," CNI Research's Ostwal said.