The performance of broilers fed diets containing feed ingredients from transgenic corn (event DP-Ø9814Ø-6 (98140; gat4621 and zm-hra genes) and transgenic soybeans (event DP-356Ø43-5 (356043; gat4601 and gm-hra genes). The 42-d feeding study compared diets produced with transgenic corn grain and soybean fractions with non-transgenic controls with comparable genetic backgrounds, or 3 commercially available non-transgenic corn and soybean combinations. Ross 708 broilers (n = 120/group; 50% male, 50% female) were fed diets in three phases: starter (d 0 to 21), grower (d 22 to 35), and finisher (d 36 to 42). Starter diets contained (on average) 63% corn and 28% soybean meal, grower diets 66% maize and 26% soybean meal, and finisher diets 72% corn and 21% soybean meal. Weight gain, feed intake, and mortality-adjusted feed efficiency were calculated for d 0 to 42. Standard organ and carcass yield data were collected on d 42. Results indicated no significant differences in weight gain, mortality, mortality-adjusted feed efficiency, organ yields, or carcass yields between broilers consuming diets produced with 98140 + 356043 and those consuming diets produced with control corn and soybean fractions. All values of response variables evaluated in the control and 98140 + 356043 groups fell within calculated tolerance intervals. Based on these results, it was concluded that the combination of genetically modified 98140 corn and 356043 soybean fractions was nutritionally equivalent to non-transgenic corn and soybean controls with comparable genetic backgrounds.