STAMP morphs–portmanteau subject-TAM-polarity morphemes–are found in numerous attested subgroups of Niger-Congo and have been proposed for at least one intermediate proto-language (Proto-Cross-River within Benue-Congo). This paper suggests that other older states in the history of Niger-Congo might also have made use of STAMP morphs, as the environment for creating such on the left edge of the verbal complex has endured for centuries in different Niger-Congo groups. Thus, different languages and subgroups have likely availed themselves of this structural option at different points in the history of Niger-Congo and this should be considered when attempting reconstruction in this domain.