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C-184/99. The application was a French national studying at a Belgian university. His application for a subsistence award was refused by the Belgian authorities on the basis that he was not a Belgian national. It was not contested that a Belgian citizen in the same circumstances would have been entitled to the award.

Had the applicant been in employment at the time of the application, it is possible he would have succeeded on the basis of rights to education granted by the provisions on Free Movement Of Workers (particularly Regulat 1612/68). However, he was not working at the time of the application, and the ECJ approached the case on the basis that he could not be deemed a worker for the purposes of the Regulation.

Until this case was heard, the ECJ had generally been reluctant to rule that the principle of non-discrimination in Art. 12 of the ECTreaty applied to education maintenance awards, although it did apply, for example, to tuition fees (e.g.,brown v secretary of state for scotland (1988), GravierVCityOfLiege1985). However, since the concept of 'citizenship' had been created by the treaty of maastricht, a different approach was required.

In Grzlczyk, the ECJ held that since Art. 17 provides that

Citizens of the Union shall enjoy the rights conferred by this Treaty...

the principle of non-discrimination was invoked whenever a citizen was exercising a right under the treaty. It was no longer necessary for a claimant to show that his circumstances were such that Art. 12 ought to apply -- any exercise of a right granted by the treaty brought Art. 12 into play.

This meant that, since a Belgian national would have been entitled to a subsistence award, refusing such an award to a French national was in breach of Art. 12.