Mumbai: State-owned ONGC on Monday became the country's most-valued company with market capitalisation of over Rs 2.42 lakh crore, surpassing Tata Group's software services company TCS.

During the morning trade, energy major ONGC commanded a market value of over Rs 2,42,890 crore, the highest for any listed company in India. This is about Rs 1,105 crore more than Tata Consultancy Services' market capitalisation of around Rs 2,41,785 crore.

ONGC stock was trading 0.49 per cent lower at 1050 hrs on the BSE. TCS was down 1.14 per cent.

On July 3, ONGC had toppled TCS to become the country's most-valued company. But its rein at the top place was short-lived, as the very next day TCS regained the slot.

Reliance Industries with a market capitalisation of Rs 2,34,785 crore was at third position, followed by Coal India (Rs 2,24,167 crore) and ITC (Rs 1,98,822 crore).

TCS was ruling the market capitalisation chart for the past two months. On May 2, the software giant had replaced RIL as the country's most valued company.

Market capitalisation, or value of a listed company is arrived at by multiplying the total number of its shares with its stock price on a particular day or time. This figure changes daily with the change in the stock price.