The 15-year-old administrator of Web site Kenton.org received a three-page letter today from the attorneys requesting he take down the materials, or face legal action.
The leak comes barely three months after the online leader released AOL 5.0, the newest version of its software. AOL 6.0, code-named K2 for Karakorum, will be released for commercial testing in May, according to the documents posted on Kenton.org.
The new service promises cosmetic adjustments to the toolbar, instant messaging and email services that are designed to make it easier for newcomers to use.
The letter warned that "prerelease of 6.0 materials that you have posted wholesale on your site are AOL's internal confidential property. These materials are not available to the public.
"You can only have obtained them from someone who breached their employment agreement with AOL or from someone who illegally hacked into AOL's system," the letter went on.
The youngster, who identified himself only as Kent, flatly denies using a third-party source or having hacked into AOL. He said he got the materials through AOL's library, which has since been blocked to outside users.
"I'm not sure what I'm going to do," he said in an interview.
AOL confirmed that it has beefed up security of its internal site.
It is not uncommon for AOL to work on new products during the spring and summer months each year so that they hit the market in time for the Christmas holidays, AOL spokeswoman Anne Bentley said today.
"This is our development time frame for the next generation of AOL products," she said.
The unauthorized papers describe new features in AOL's instant messaging service that included a pull-down bar with different facial expressions a person can send to buddies.
Other upgrades appear in the toolbar. But early research based on the response of eight test subjects who compared the 6.0 version to AOL's 5.0 stated that most preferred a combination of the two services.
Some of the test subjects said the newer toolbar appeared poorly organized compared with the groupings on the 5.0 toolbar, according to the study.
It's likely, however, that these features will change as the software is further developed.
"It's a very long time between now and the time when it will be released to the public," Bentley said. "We're constantly fine-tuning the product."
AOL employees will be able to download 6.0 on Feb. 1. Commercial testing begins in May, and the product is scheduled for public release in August.
Only three months ago, AOL 5.0the market with new features such as a photo station, an online calendar, a revamped search engine, a shopping channel, and a service for broadband applications.
While executives played up the new release, some analysts said the changes were minor upgrades to its previous software.
Nonetheless, Bentley said that about 8 million subscribers already have downloaded 5.0.