The shares opened at 414 yen on the Tokyo Stock Exchange, down by their daily loss limit of 100 yen, representing a 19.45 percent fall.
Panasonic said after the market closed Wednesday that it would book a $9.6 billion net loss for the year to March 2013 as it undergoes a major overhaul of its troubled business.
While it said it would achieve an operating profit, restructuring costs and writedowns would result in the whopping 765 billion yen shortfall and Panasonic warned that regular dividends to shareholders would be temporarily shelved.
The projected loss is close to Panasonic's record 772.2 billion yen shortfall last fiscal year, one of the worst-ever for a Japanese firm, and a reversal of its earlier vow to return to the black by March next year.
Panasonic, like rivals Sony and Sharp, which report earnings later Thursday, has suffered in its television business amid falling prices and stiff competition from overseas rivals, while a strong yen has also hit Japanese manufacturers.
The television business has razor-thin profit margins and Japanese firms have been unable to keep pace with rivals such as South Korea's Samsung Electronics.
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