It was in those circumstances that, on 6 September 1991, Ajinomoto and NutraSweet each brought proceedings for annulment of Regulation No 1391/91 and for the return of the provisional and definitive antidumping duties paid under that regulation and under Regulation No 3421/90.
1391, che istituisce un dazio antidumping definitivo sulle importazioni di aspartame originario del Giappone e degli Stati Uniti d'America.