Oct. 3 (Bloomberg) -- The U.S. Securities and Exchange Commission is investigating the origin of a false report on a CNN citizen journalist Web site that Apple Inc. Chief Executive Officer Steve Jobs had a heart attack and was hospitalized.

The agency's enforcement unit is trying to determine whether the iReport.com posting was intended to push down the company's stock price. CNN is cooperating with the SEC's probe, network spokeswoman Jennifer Martin said. The report is ``not true,'' Apple spokesman Steve Dowling said in an interview.

Concern about Jobs's health weighed on the shares this year, contributing to a 51 percent drop. The stock swing caused by today's erroneous report drew renewed calls for Apple, which has said only that Jobs's health is a ``private matter,'' to be more forthcoming, said Jeffrey Sonnenfeld, senior associate dean at Yale University's School of Management.

``Leaving it to rumor and speculation is reckless,'' said Sonnenfeld, who has personally owned Apple shares since 1997, the year Jobs returned as CEO. ``If he is healthy, they should say so. If he's not, we should know that too.''

The shares fell as much as 5.4 percent earlier today after the post on iReport.com cited an anonymous source saying Jobs was rushed to the hospital after suffering a ``major heart attack.'' The report has been removed.

John Heine, a spokesman for the SEC, declined to comment.

Apple, based in Cupertino, California, dropped $3.03, or 3 percent, to $97.07 at 4 p.m. New York time on the Nasdaq Stock Market. The stock earlier fell to $94.65, the first time it has traded at less than $100 since May 2007.

Unedited. Unfiltered. News.

Jobs, who had surgery four years ago to treat pancreatic cancer, appeared visibly thinner at a company event in June, raising speculation he was ill. Apple said at the time that Jobs was suffering from a ``common bug'' and has declined to comment further on his health.

Dowling declined to comment further today.

Time Warner Inc.'s CNN, based in Atlanta, describes iReport.com as a place for ``Unedited. Unfiltered. News.'' and said it ``makes no guarantee about the content or coverage'' on the site.

Content is ``entirely user-generated,'' said CNN spokeswoman Jennifer Martin.

``After the content in question was uploaded to iReport.com, the community brought it to our attention,'' Martin said in an e- mailed statement. ``The fraudulent content was removed from the site and the user's account was disabled.''

Short Sellers

Jobs, 53, told members of Apple's board in July he is cancer-free and dealing with nutritional problems after his cancer surgery, which can lead to weight loss, the New York Times reported at the time, citing people close to Jobs.

Last month, Jobs told cable network CNBC he is healthy and blamed concern about his health on hedge funds that are shorting the stock. Shorting, or short selling, is the practice of selling borrowed shares and betting on repurchasing them later at a lower price.

The stock would plummet 25 percent if Jobs, who is considered the heart of Apple's product design and marketing efforts, were to leave for any reason, said Gene Munster of Piper Jaffray & Co. in Minneapolis. That would erase about $21 billion from Apple's market value.

``It's a tough position to be in -- they don't continually want to field questions and make news when there is no news,'' said Ryan Jacob, who manages the Jacob Internet Fund and has owned Apple's shares since 2003. ``We as investors have to hope that if there is something material to say, they will comment quickly.''

Shadow

``Concerns about Steve Jobs's health in 2008 have shadowed what otherwise appears a stellar year for Apple,'' said Hakim Kriout, an analyst at municipal bond trading and underwriting firm Grigsby & Associates in New York, which owns Apple shares. ``Investors worry that without Jobs, the company will falter.''

Demand for Apple's iPhone, Macintosh computer and iPod media player may drive annual sales to more than $30 billion for the first time this year, according to analysts surveyed by Bloomberg. Apple will report its fiscal 2008 results this month.

``Given the circumstances, there needs to be much greater transparency here on this particular issue,'' said Charles Elson, director of the Weinberg Center for Corporate Governance at the University of Delaware in Newark.

Cook, Oppenheimer

Apple hasn't announced a succession plan should anything happen to Jobs. In March, Jobs told investors at the annual meeting that the board would have a variety of executives to choose from were he to step down.

He highlighted the long tenure of top Apple managers and singled out Chief Operating Officer Timothy Cook and Chief Financial Officer Peter Oppenheimer as potential leaders. Cook stood in for Jobs during a monthlong leave in 2004 while he recuperated from his cancer surgery.

``It's my job as the CEO to do my best to make sure everybody on the executive team is a potential successor to me,'' Jobs said March 4. ``We've got great talent and I think the board would have a few really good choices. We talk about that a lot.''

Announcing a succession plan may not be enough to erase concern about Jobs, Jacob said.

``I'm sure internally there is a succession plan in place as with most companies, but I'm not so sure that would make a big deal to investors because they feel that Steve Jobs has been so important,'' Jacob said. ``If something happens to Steve Jobs, something happens to Steve Jobs.''

To contact the reporter on this story: Connie Guglielmo in San Francisco at cguglielmo1@bloomberg.net

Last Updated: October 3, 2008 18:33 EDT