The proposal presented meets the requirements of art. 10 of Normative Resolution No. 5; NK603 x T25 corn provides Brazilian farmers with the possibility of using two herbicides with different modes of action to control weeds and as a weed resistance management tool; NK603 x T25 corn is currently approved in the United States, Canada, Japan, Mexico, South Korea, Philippines, Colombia and Taiwan; The results presented for the individual events ( NK603 corn and T25 corn, already approved by CTNBio, the data and information presented in this Biosafety Report, as well as the information currently available in the scientific literature; Human and Animal Health Areas manifested for granting the commercial release request. A specific study was carried out to evaluate the vigor and germination of NK603 x T25 corn, when compared to the control corn and to the range of values ​​of commercial references. The grains were collected in the plots that made up the above mentioned experiment. No significant differences were detected between NK603 x T25 maize and the control for germination percentage, either in the individual analysis by site or in the joint analysis of the five sites. Regarding vigor, in the individual analysis by location, significant differences were detected between NK603 corn and the control in the Não-Me-Toque (92.75 vs. 96.25%) and Sorriso (78.75 VC. 85, 00%). However, these values ​​are within the range of vigor of commercial references and, within the expected due to the intrinsic genetic variability of the corn crop. No significant differences were observed in the joint analysis of the five sites. Another study was carried out to evaluate the potential for grain germination and growth of corn as a volunteer plant from grains produced in the five Monsanto Experimental Stations, in the 2011/2012 harvest. The grain samples of NK603 x T25 corn, together with those of conventional temperature and humidity control corn, in a greenhouse. The evaluations took place every 15 days, when the volunteer plants were counted and uprooted. In the individual analysis by location, a significant difference was detected between NK603 x T25 corn and the control (9.38 vs. 7.63%), for the number of plants emerged from the grain samples from Santa Cruz das Palmeiras. However, the value is within the range of commercial references. In the joint analysis, no significant difference was observed. The agronomic and phenotypic observations carried out allow us to conclude that NK603 x T25 maize does not consistently differ from the control maize. Taken together, the data show that NK603 x T25 maize does not pose a greater risk as weeds and does not result in a risk to the environment when compared to conventional control maize.