This article discusses the potential legal obligations of researchers who obtain cultural, technological, religious or mystical knowledge from Indigenous custodians. It is argued that the combination of four existing areas of law: confidential information, equitable estoppel, statutory prohibitions against misleading or deceptive conduct, and unjust enrichment may in effect provide a comprehensive protection to Indigenous peoples against the misuse of knowledge they share with researchers, even without sui generis law or international treaties. Unlike previous approaches to this topic, this paper is not proposing new legal concepts. The obligations discussed are already present in most common law jurisdictions. Affected researchers may be surprised at the extent of this protection, and the commensurate extent of their legal obligations. Research institutions may find themselves being held accountable for not having complied with these responsibilities. An outline of one mechanism to formalise and make clear researcher responsibilities is provided. It is hoped that such a mechanism will aid researchers and research institutions in fulfilling their legal and moral responsibilities in regard to Indigenous knowledge.