Dragged down by heavy selling in the shares of RIL and TCS, the combined market capitalisation (m-cap) of eight most-valued Sensex companies fell by Rs 43,430 crore in the past week.
On the other hand, the list of gainers included NTPC and Infosys.
The m-cap of RIL plunged Rs 13,015 crore to Rs 2, 66,486 crore, taking the biggest hit among the top-10 companies.
Shares of the energy major also dipped 4.65 per cent to Rs 825.15 during the period under review (August 8-August 16).
TCS's market value plunged Rs 12,888 crore to Rs 3,48,424 crore, becoming the second biggest loser in the elite list.
The m-cap of Coal India dropped by Rs 6,221 crore to Rs 1,63,183 crore. HDFC Bank lost Rs 5,161 crore to Rs 1,40,852 crore.
ITC's market value dipped Rs 4,270 crore to Rs 2,53,093 crore and ONGC shed Rs 1,027 crore to Rs 2,32,623 crore. Telecom major Bharti suffered an erosion of Rs 620 crore to Rs 1,34,252 crore and HUL's m-cap fell by Rs 228 crore to Rs 1,29,423 crore.
In contrast, NTPC added Rs 1,814 crore to Rs 1,15,106 crore in its market-cap and Infosys saw a surge of Rs 775 crore to end the week at Rs 1,70,812 crore in m-cap.
In the ranking of top-10 most valued companies, TCS continued to rule the charts, followed by RIL, ITC, ONGC, Infosys, CIL, HDFC Bank, Bharti, HUL and NTPC.
The benchmark S&P BSE Sensex had on Friday tanked by 769.41 points. During the past week, the index had lost 1.84 per cent or 348.8 points to end at 18,598.18 as Friday's steep losses came after four straight days of gain.
Market capitalisation or the 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.