In order to address environmental and climate change in a sustainable manner, it is necessary for corporations to make commitments in accordance with sustainable principles, which can be communicated through the use of indicators. In certain cases, indicators are subject to manipulation for the benefit of corporations, a strategy also referred to as "greenwashing". One method of misleading is the transfer of non-sustainable activities of a company to other collaborating companies. This paper proposes and defines the Sustainability meta-Indicator (SmI) which can serve as a tool for the assessment of misleading sustainability claims. Its value depends on the sustainability indicators of the other collaborating companies where the company in question pays money and the corresponding amount of paid money. The results of the use of SmI on synthetic data demonstrate that the proposed meta-indicator facilitates the assessment of misleading sustainability claims. Additionally, it can be used as a communication mechanism to enhance the value of companies and to support new partnerships and business strategies. For policymakers, this meta-indicator serves as a tool to support measures against consumer misinformation and deception.