The utility of active transposons from maize (Ac/Ds), rice (mPing) and tobacco (Tnt1) in tagging soybean genes has been demonstrated [11–13]. However, this approach requires genetic transformation. Handling thousands of transgenic lines in the field prior to deregulation is impractical and cumbersome. Furthermore, products generated through genetic transformation are often not well received by a significant proportion of the end users worldwide and the deregulation step could be lengthy and expensive. Tagging of soybean genes using an endogenous transposable element is therefore an attractive solution not only for functional analyses of tens of thousands of soybean genes, but also in generating desirable mutants for rapid genetic improvement of important traits in the commercial soybean cultivars. Since mutants created by an endogenous transposon are not GMOs, the products produced from incorporation of such mutants should be accepted by all consumers.