On January 23, 2017, FDA published “Tobacco Product Standard for N-nitrosonornicotine Level in Finished Smokeless Tobacco Products” in which they proposed an NNN ceiling of 1.0 ppm (DWB) through the end of product shelf life. During the past several decades substantial efforts have been made by the tobacco industry and academic institutions to reduce NNN levels and its precursor nornicotine in tobacco products. Research on the mechanism of nornicotine formation led to the identification of three tobacco genes (CYP82E4, CYP82E5 and CYP82E10) encoding for cytochrome P450 nicotine demethylases that convert nicotine to nornicotine. Through conventional breeding, we developed dark tobacco varieties (Stable Reduced Converter/SRC varieties) containing the three non-functional nicotine demethylase genes. Tobacco varieties containing this new technology, named ZYVERT^® technology, were grown in different locations for on-farm research tests for 3 years and showed an averaged NNN reduction of 74 %. In 2017 Altria Client Services contracted with growers in Kentucky and Tennessee for production of about 3.5 million pounds total of dark air-cured and dark fire-cured SRC variety incorporating ZYVERT^® Technology. Tobacco bales from the SRC tobacco variety and commercial low converter (LC) varieties were sampled at delivery and analysed for TSNAs and alkaloids. NNN reductions in the SRC crop averaged 53 % and 68 % in dark air-cured and dark fire-cured, respectively, compared to the LC crop.