Three petitions had been filed challenging the Anandiben Patel-led government notification, which came in April in a bid to placate the protesting Patidar community.
The quota would have been granted to families with an annual income of less than Rs six lakh.
Petitioners had argued that the ordinance was contrary to precedents established by the Supreme Court for other backward classes on the recommendation of the Mandal Commission in 1990. Currently, Gujarat has a 49 per cent reservation for scheduled castes (SC), scheduled tribes (ST) and other backward class (OBC).