From Bloomberg: Moody’s Japan K.K. cut its rating on Tokyo Electric and warned it may reduce it further, saying the problems at Fukushima “appear far from being resolved” and the company is likely to remain unprofitable for a long time. Senior secured and long-term issuer ratings were downgraded to Baa1 from A1, Moody’s said in a statement.
"Tokyo Electric’s shareholders may be wiped out by clean-up costs and liabilities stemming from the nuclear accident, the worst since Chernobyl. The company, known as Tepco, faces claims of as much as 11 trillion yen if the crisis lasts two years and potential takeover by the government, according to a March 29 Bank of America Merrill Lynch report."