Stocks that are moving substantially or trading heavily Thursday on the New York Stock Exchange and Nasdaq:

NYSE

Arcelor Mittal, up $2.63 at $99.63

The world’s largest steel maker posted a 5 percent jump in first-quarter profit, but an executive warned rising prices may pressure demand and the industry.

CBS Corp., down 66 cents at $24.16

It will spend $1.8 billion in cash, the equivalent of $11.50 per share, for online media company CNET Networks Inc. in a move to bolster its Internet presence.

General Motors Corp., up 59 cents at $20.78

The automaker and the Canadian Auto Workers union have inked a new contract that will freeze wage increases for three years, but include cost-of-living adjustments.

J.C. Penney Co., up $1.86 at $46.11

The retail icon’s first-quarter profit slumped nearly 50 percent as consumers tightened their wallets, and the company guided for a “difficult” 2008.

The Blackstone Group, up 27 cents at $19.77

The mammoth private equity fund, which went public about a year ago, posted its second consecutive quarterly loss as the credit and leveraged buyout markets shrank.

Blockbuster Inc., up 11 cents at $3.18

The movie rental chain swung to a first-quarter profit as domestic sales grew, a positive sign ahead of its planned buyout of Circuit City Stores Inc.

NASDAQ

Ctrip.com International Ltd., down $5.41 at $57.92

One of China’s largest travel Web sites faces a “perfect storm” after a catastrophic earthquake paralyzed the nation and ahead of Olympic travel restrictions, an analyst said.

Yahoo Inc., down 16 cents at $26.98

Billionaire investor Carl Icahn has launched a proxy battle to replace the Internet portal’s board of directors after it rebuffed Microsoft’s takeover efforts.

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