The attacking midfielder, who is being linked with a move to Major League Soccer, is a free agent in June and Hamburg CEO Dietmar Beiersdorfer has intimated that the 32-year-old will not be extending his stay at the Bundesliga club.
Defensive trio Marcell Jansen, Heiko Westermann and Slobodan Rajkovic are also entering the final months of their deals at the Imtech Arena.
Beiersdorfer told the club's official website: "We have already talked with Rafael van der Vaart, Marcell Jansen, Heiko Westermann and Slobodan Rajkovic about our planning.
"Rafael and Marcell know that we are not to communicate about a contract extension with them.
"Heiko and Slobodan, we have postponed the decision and communicated it to the players as well."
Van der Vaart, who Beiersdorf has hinted could be offered a possible future coaching role at Hamburg, is in his second spell at the club, having rejoined from Tottenham in August 2012.
Sporting Kansas City earlier this month confirmed an interest in signing Van der Vaart, who will be determined to depart after helping Hamburg preserve their Bundesliga status, with the side 16th.
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