At close of trade on the BSE, the market capitalisation (m-cap) of TCS was at Rs 6,19,499.95 crore, which is Rs 5,320.02 crore more than that of RIL's Rs 6,14,179.93 crore valuation.
RIL shares witnessed selling pressure, falling 3.97 per cent to close the day at Rs 968.85. During the day, it tumbled 4.72 per cent to Rs 961.20.
However, decline in shares of TCS was not that sharp as it fell 0.44 per cent to Rs 1,650.95 at close.
On March 9 also, Tata Consultancy Services had raced past RIL to become most valued domestic firm by m-cap.
A heavy sell-off in the equity market since past few days has pulled down RIL's market valuation sharply. RIL shares fell for the third consecutive day on Wednesday, dropping 12.47 per cent and wiping out Rs 87,506.07 crore from its market valuation in three days.
Last week also, Reliance shares came under massive selling pressure amid plunge in international oil prices.
In just about four months, Reliance Industries m-cap has slumped from the highs of Rs 10 lakh crore it hit in November last year.
RIL and TCS have in the past also competed with each other for the number one position in terms of market capitalisation.
At close of trade on Wednesday, the market capitalisation chart was topped by TCS followed by RIL, HDFC Bank, HUL and HDFC.
The m-cap figure of companies changes daily with the movement in their stock prices. SUM SHWSHW