Despite earlier predictions, that we discussed previously, that AOL’s patent portfolio could be worth as much as $1 billion, the latest estimates put the value at about $290 million.

AOL has been under fire from Starboard Value LP, one if its largest shareholders with 5.2% of the company’s stock, to monetize the 800 patents in its portfolio.  Starboard has also attempted to place a so-called “patent troll” on the AOL board to expedite the process.

AOL has hired its own expert, Evercore Partners, Inc., to find a buyer for its patents, which are in fields including internet advertising, shopping, navigation, and communications.

According to David Pratt, president of M-Cam (a company that assesses markets for intangible property), $290 million is the “absolute ceiling price.”

Pratt said,  “It’s worth much less than what investors have estimated, based largely on the fact that most of AOL’s patents are not commercially viable, or junk grade.”

However, several commentators noted the difference between the pure financial value of the patents and their long-term strategic value as a source of licensing revenue.  An investor focused on the latter might bid the portfolio back up to the billion dollar estimate.

AOL is also exploring other options, such as taking the company private or merging with Yahoo.

When AOL acquired Time Warner in 2000, the combined companies had revenues of $30 billion per year.  When the companies de-merged in 2009, annual revenues had fallen to $3.2 billion.  For the first quarter of 2012, AOL revenues are projected to be $526.1 million, according to Bloomberg.