Seven of the top-10 most valued companies lost a total of over Rs 23,000 crore from their market capitalisation during the result season last month, while firms including Reliance Industries and NTPC saw their valuations rise.

Mukesh Ambani-led Reliance Industries' (RIL) market valuation rose by Rs 4,839.65 crore, taking its total market cap to Rs 3,46,440.26 crore for the month ended October 31.

RIL had a market valuation of Rs 3,41,600.61 crore at the beginning of the month, on October 1, 2009.

Second comes oil firm ONGC, which witnessed a value erosion of Rs 2,277.9 crore during the month. Its market cap stood at Rs 2,50,525.84 crore.

State-run NTPC inched up to the third slot by adding Rs 2,762.23 crore pushing trading firm MMTC that lost Rs 9,636.25 crore to the fourth position.

The total market valuation of NTPC surged to Rs 1,76,205.48 crore, while MMTC's dipped to Rs 1,70,186.25 crore.

Moving further, private telecom services provider Bharti Airtel lost Rs 6,378.69 crore from its market valuation, however state-run mining giant NMDC added Rs 1,129.77 crore to its market cap.