This article assesses different approaches currently discussed and developed in international human rights and investment law to establish investor obligations. The article begins with a general framework of analysing and comparing these approaches. Next, attempts to include direct obligations of business entities in international human rights treaties are discussed. Despite earlier indications the recent initiative to create a legally binding instrument on business and human rights will most likely not include direct obligations for business entities. Subsequently, the article assesses the development of investor obligations in new international investment treaties and through the interpretation and application of existing international investment agreements. Arguably, the former will not lead to binding obligations in the foreseeable future and the latter rests on methodologically questionable grounds. Consequently, the article suggests that the way forward will require domestic legislation in host and home states to establish investor obligations which can be taken into account when interpreting existing investment treaty clauses requiring the investor to adhere to domestic law. This would reflect recent trends both in investment law reforms as well as the business and human rights movement.