Upon opinion of the European Food Safety Authority (which concluded that, under the proposed conditions of use, L-cystine does not have an adverse effect on animal health, human health or the environment and that it may be considered efficacious to contribute to the requirements for sulphur- containing amino acids in all animal species) this regulation authorizes the use of L-cystine as an additive in feeding for all animal species. The Annex specifies the conditions of use to be complied with.