Toni Sacconaghi just won’t give up.

For more than two years, Bernstein Research’s top Apple (AAPL) analyst been after Steve Jobs to spend some of the company’s growing cash hoard ($51 billion as of September), preferably on a stock buyback or cash dividend.

“Shareholder frustration,” he wrote in an open letter to the board of directors in August, “is bordering on exasperation.”

Now he’s come up with a new argument. So many institutional asset managers already own Apple, he says, that unless the company starts distributing some of that cash to shareholders, there will be nobody left to buy the stock.

“Currently,” he wrote in a note to clients earlier this week, “Apple is the second largest company by market cap and the fourth most favorably recommended stock by sell-side analysts in the S&P 500. These characteristics have led many investors to question whether Apple’s stock can continue to materially outperform, and who incremental buyers for the stock might be.”

Sacconaghi’s case rests on a survey he made of large-cap growth and value funds — groups that accounted for 32% and 41%, respectively, of the nearly $2 trillion in managed assets in 2009.

He found that Apple was held by 9 out of 10 top growth funds, representing nearly 6% of their total portfolios. By contrast, the stock was held by none of the top 10 value funds he examined.

“So why is Apple ostensibly widely under-owned by value fund managers?” he asks rhetorically. He offers four answers:

1. The company’s revenue base is largely transactional, in contrast to companies like HP, Oracle, and IBM, which derive a high portion of their profits from recurring revenue sources (typically annuity support or software maintenance streams);
2. Apple’s risk of technology obsolescence is high, relative to other companies;
3. investor sentiment is very positive, while value managers typically seek out-of-favor names (though Oracle is a notable exception here); and
4. Apple has no track record of returning cash to its shareholders, nor has it articulated a plan for returning cash to shareholders. (emphasis ours)

Like we say, Toni Sacconaghi just won’t give up.

NOTE: Bernstein is the sell-side research arm of AllianceBernstein, which sold more than 2 million shares of Apple last quarter but still holds 11.18 million shares worth nearly $3.6 billion at Wednesday’s closing price. (Thanks to reader Jim Neal for pointing out the connection.)

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