In line with the broader market, shares of ONGC on Tuesday surged nearly one per cent to touch an intra-day high of Rs 1,415 thus, fuelling the market capitalisation of the firm to a whopping Rs 3,00,511 crore (Rs 3,005.11 billion) in the morning trade.
Reliance Industries' market cap stood at Rs 3,38,883 crore (Rs 3,388.83 billion) and retained its position as the most valued company.
The shares of the company, however, were trading in the negative territory and dipped 0.36 per cent at Rs 1,036 in morning trade.
ONGC investors got richer by as much as Rs 555 crore (Rs 5.55 billion) in just over two hours of trading as the market valuation of the company stood at Rs 2,99,956 crore (Rs 2,999.56 billion) at the end of trade on Monday.
Analysts said the rally in the broader market and sustained inflows of overseas funds, bolstered the stock.
The BSE benchmark Sensex shot up by over 135 points to regain the magical 20,000-level in the opening trade on Tuesday for the first time since January 17, 2008, on spurt in buying of oil and gas, capital goods and banking sector stocks.
Similarly, the wide-based National Stock Exchange also crossed the crucial 6,000 points to trade 36.40 points higher at 6,016.85 points.
Both indices have regained these levels after almost 32 months.
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