Time Warner may be worth about 46% more if disgruntled shareholders led by Carl Icahn force a breakup of its assets.

The businesses, which include America Online and cable-TV systems, would be worth a total of at least $27 a share if they were separated, according to valuations by analysts including Michael Kupinski at AG Edwards & Sons. Time Warner shares fell 30 cents to $18.24 at in New York Stock Exchange composite trading.

Time Warner shares are trading at the same level as in 2002, prompting Mr. Icahn, a Time Warner shareholder and activist investor, to consider forming a group to press the board to spin off Time Warner Cable and other divisions. Mr. Icahn told investors the shares may be worth $27 if the company also buys back as much as $15 billion in stock, the New York Times reported.

“I expect management to look at ways to close the gap between market value and intrinsic value,” the head of research at Chicago-based Harris Associates LP, Time Warner’s 12th biggest shareholder with 71.1 million shares, Henry Berghoef, said. Harris also values Time Warner at $27, he said. “If there’s a gap that persists over time, they should do things to close it. If someone offers them a price for something, that ought to be considered.”

“Management is doing everything it can and is committed to creating value for shareholders,” a Time Warner spokesman, Ed Adler, said. Mr. Icahn didn’t return calls seeking comment.

Time Warner shares had fallen 9.8% this year before reports that Mr. Icahn was buying. They have lagged behind the 1.6% rise in the Standard & Poor’s 500 Index, even as Chief Executive Officer Richard Parsons, 57, settled lawsuits and agreed to buy Adelphia Communications assets. He plans to sell cable shares to the public. The stock had jumped 5.6% in three days on speculation Mr. Icahn was planning to challenge Mr. Parsons’s plans.

Separating assets would unwind a company that was built over 20 years and includes assets such as Fortune and Time magazines and the Cable News Network.

The company bought Ted Turner’s cable-TV assets for $7.3 billion in 1996. That was followed in 2001 by a $124 billion merger with AOL. The combination failed to generate the promised growth and the shares have since tumbled by two thirds. Time Warner last week set aside $3 billion for shareholder suits related to the transaction.

The board last week said it will buy back shares valued at $5 billion, its first repurchase since 2001, and Mr. Parsons plans to sell part of the cable business next year.

Mr. Icahn, who owned 5.1 million shares of Time Warner as of March, is seeking to lead a group including hedge fund managers to press Time Warner to alter its strategy, the New York Times said.

Mr. Icahn, 68, has amassed more than $7 billion over 40 years by investing in companies from Trans World Airlines to Revlon and taking on management. He has made a career of forcing change at companies.