Shares in TEPCO tumbled 15.82 per cent in Tokyo Wednesday amid uncertainty over a bill aimed at ensuring the troubled utility can pay compensation over the Fukushima Daiichi nuclear crisis, dealers said.
"The bill is written in a manner that can be interpreted in any number of ways. In the end, it will come down to a political decision" regarding whether shareholders will be required to take responsibility for the firm's liabilities, Monex market analyst Toshiyuki Kanayama told Dow Jones Newswires.
The bill still needs to pass both houses of Japan's parliament. Tokyo Electric Power Co. shares closed at 431 yen Wednesday.
Dealers say shares are facing profit-taking since they had already risen in recent weeks on prior expectations of the bill's passage, but remain around 80 per cent lower than pre-earthquake levels.
Tens of thousands remain evacuated from homes, farms and businesses in areas within 20 kilometres (12 miles) of the Fukushima plant that has been leaking radiation since the March 11 tsunami disabled cooling systems, sparking meltdowns.
Some analysts put the cost of compensation as high as 10 trillion yen ($128.4 billion).
Japanese media reported that a draft of the compensation plan will widen the scope of TEPCO's liabilities and make it pay damages for the cancellation of reservations by tourists from overseas due to the crisis.
The government panel drafting the guidelines will recognise lost revenue that resulted from the cancellations by the end of May in regions where the government did not issue evacuation orders, Kyodo news said.