Stewart confirmed that a late bid from an Eastern European club was rejected this summer, but wouldn't comment on the amount.
"He is developing great. He is a target for the team, plays good football and translates that also in goals," AZ director of football and former U.S. international Earnie Stewart told the club's official website.
"Last summer there was indeed a bid for Jozy from a wealthy country in Eastern Europe," Stewart said. "This bid, however, came at a very late stage in which we could not adequately act in terms of attracting a possible successor. For us it was not interesting enough.
"Jozy was happy to remain AZ. He has, after years of wandering, found a home. He doesn't want just any club move."
The rumored amount of the bid was eight millions euros, but Stewart refused to comment on any monetary figures.
After a stuttering start to his European career, Altidore broke out with 19 goals in all competitions last year in his first season with AZ. He is off to another strong start in the 2012-13 campaign, with nine league goals already, good for second in the Eredivisie.
If Altidore is to leave AZ, some of Europe's biggest clubs could be in play, as Stewart indicated that many of them scout AZ matches.
"This season, there have been scouts of big clubs like Barcelona, Bayern Munich, Chelsea and Tottenham Hotspur in the AZ gallery," Stewart said.
Stewart knows that come the winter transfer window, or the summer window after that, he could be losing one of his biggest assets.
"I do not exclude that come this winter or at the end of the season, there will be more interest in Jozy," Stewart said.
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