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An investigation into the precise ethylenediaminetetraacetic acid (EDTA) crystalline structural report was initiated, as there appeared to be some ambiguity regarding the accurate notation of EDTA as a neutral molecule or a zwitterion. As a result, the first and foremost article reporting EDTA in zwitterionic form was determined after a difficult confirmation. Additionally, crystallographic data of the zwitterionic EDTA itself and non-chelated salts thereof registered on the CCDC were also mentioned herein. This episodic knowledge will be fundamental for not only chemical education but also related science and technology in the future.