Mumbai: Within days of losing its position as the country's most valued company to state-run Coal India, billionaire Mukesh Ambani-led Reliance Industries on Friday briefly slipped below another PSU major ONGC to the third position in the market valuation charts.

State-run ONGC pipped corporate giant Reliance Industries (RIL) in late morning trade to emerge as the country's second-most valued company with a slightly higher market valuation, but could not retain the lead for the entire day.

ONGC shares pared their intra-day gains later in the trading session and the company's market valuation slipped below that of RIL at the time of the market close.

At around 1145 hours, ONGC commanded a market valuation of Rs 2,38,528 crore at the BSE, which was a little over Rs 600 crore higher than that of RIL.

RIL's market value stood at Rs 2,37,882 crore at that time, as its shares were trading 1.81 per cent down on the bourses. In contrast, the ONGC stock was trading with a gain of 1.07 per cent at the BSE.

However, ONGC shares pared their gains and closed with a marginal fall of 0.04 per cent -- commanding a market value of Rs 2,35,917 crore at the BSE.

In comparison, RIL's market value stood higher at Rsm 2,39,402 at the market close, despite the shares settling with a 1.2 per cent fall for the day.

At the same time, Coal India Ltd (CIL) shares closed with a gain of 0.8 per cent and maintained its top position with a market capitalisation of Rs 2,48,675 crore.

At the end of Friday’s trade, CIL had a market cap of Rs 2,46,780.36 crore, followed by RIL at the second position (Rs 2,42,267.27 crore) and ONGC at third (Rs 2,36,003.02

Earlier on August 17, CIL had toppled Reliance Industries as the country's most valued firm, thus ending the private sector corporate giant's over four-year reign at the top of the market valuation charts.

Interestingly, RIL had toppled state-run ONGC over four years ago to become the country's most valued firm, but slipped below two public sector firms in terms of market valuation in intra-day trade on Friday.

 A company's market valuation, or market capitalisation, is determined by multiplying its share price by the total number of shares.

CIL and ONGC had been closing the gap on RIL in terms of market valuation for the past few weeks, as RIL's stock has been under selling pressure and the two PSUs have been mostly performing well even in a weak market.