TOKYO — To say that Yui Kimura is a distressed investor might be an understatement: She is a small shareholder in the operator of the nuclear power plant at Fukushima, Tokyo Electric Power, whose shares have lost nine-tenths of their value.

Now, she would like the company to at least face up to its responsibilities to the more than 100,000 people who have been driven from their homes after the tsunami disaster. She co-sponsored four resolutions at the annual shareholders’ meeting Wednesday, including one demanding that the company decommission all of its nuclear reactors.

“As the company behind a devastating disaster, we feel it needs to go that distance,” she said.

Ms. Kimura is part of an emerging breed of individual Japanese investors who are starting to break the traditionally docile ranks of shareholders and hold company managers accountable, for issues like missed management targets and corporate scandals.

Shareholder meetings this summer have been marked by a flurry of proposals from investors challenging the management — opposing board appointments, for example, or simply expressing anger at executives.