The warnings have battered semiconductor shares, among them TSMC, as Mr. Chang's company is widely known, and Intel, the Silicon Valley global chip giant.

The warning, announced after the market closed on Thursday, helped drag down other semiconductor shares yesterday, including Intel and Micron Technology.

Other semiconductor shares also increased.

The easing of technology-stock prices has come in waves, starting with semiconductor shares last fall.

First, semiconductor shares, which often lead the action in tech stocks, have gone into a nose dive.

Still, losses in semiconductor shares were limited because investors were braced for bad news.

What strikes some as peculiar about the current stampede into semiconductor shares is that worldwide sales of chips are expected to rise just 14 percent this year over last.

Investors piling into semiconductor shares may not know that many insiders at these companies are exiting.

Once overexposed to technology stocks, he sold $10 billion of semiconductor shares in November and another $8.5 billion in December.

The stock market moved mostly higher yesterday in a sluggish session highlighted by options-related trading and a sharp selloff in semiconductor shares.