Compositional equivalence of crops improved through biotech-derived transgenic, or genetically modified (GM), traits and their conventional (non-GM) comparators is an important criterion in breeding as well as a key aspect of risk assessments of commercial candidates. We present here an analysis evaluated from compositional data on GM corn and GM soybean varieties grown across a range of geographies and growing seasons with the aim of not only assessing the relative impact of transgene insertion on compositional variation in comparison with the effect of environmental factors but also reviewing the implications of these results on the safety assessment process.