The European Commission asked EFSA for an opinion on the safety for the target animals, consumer, user and the environment and on the efficacy of a L-lysine monohydrochloride (HCl, minimum 98.5%) and of a concentrated liquid L-lysine (base, minimum 50%) produced by genetically modified strains of Corynebacterium glutamicum (NRRL-B-67439 or NRRL B-67535). They are intended to be used in feed or water for drinking for all animal species and categories. Neither viable cells of the production strains C. glutamicum strains NRRLB-67439 or NRRL B-67535; nor their recombinant DNA were detected in the final products. Therefore, those products do not pose any safety concern associated with the genetic modification of the production strains. L-Lysine HCl and concentrated liquid L-lysine (base) produced by C. glutamicum strains NRRLB-67439 or NRRL B-67535 are considered safe for the target species, for the consumer and for the environment. L-Lysine HCl produced by C. glutamicum strains NRRL B-67439 or NRRL B-67535 is considered not irritant to skin or eyes and not a skin sensitiser. In the absence of data, the FEEDAP Panel cannot conclude on the potential toxicity by inhalation of L-lysine HCl produced by C. glutamicum strains NRRL B-67439 or NRRL B-67535. Concentrated liquid L-lysine (base) produced by C. glutamicum strains NRRL B-67439 or NRRL B-67535, due to its high pH (10.7 and 10.9, respectively) is anticipated to be corrosive to skin and eyes and poses a risk by inhalation. L-Lysine HCl and concentrated liquid L-lysine (base) produced by C. glutamicum strains NRRLB-67439 or NRRL B-67535 are considered as efficacious sources of the essential amino acid L-lysine for non-ruminant animal species. For the supplemental L-lysine to be as efficacious in ruminants as in non-ruminant species, it would require protection against degradation in the rumen.