Van Gaal had been named as a director by four members of the club's board - Edgar Davids, Steven ten Have, Paul Romer and Marjan Olfers - last November.
However, Cruyff, who is also part of the board, said the quartet had kept him in the dark when they appointed Van Gaal - a long time rival of the Netherlands great.
The Amsterdam court ruled that the naming of Van Gaal was not on the agenda for the board meeting and therefore Cruyff, who was absent, could not have known the importance of the event.
Cruyff was joined by a dozen youth coaches including Dennis Bergkamp, Jaap Stam, Ronald de Boer and Wim Jonk in protesting the appointment of former Bayern Munich coach Van Gaal, who won the European Cup with Ajax in 1995.
On Friday, an Ajax shareholders meeting will take place when the board will be brought to task.
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