In January 2022, the UK National Contact Point (UK NCP) issued a final statement in a specific instance claim brought against Bonsucro, a multi-stakeholder initiative (MSI) that aims to promote sustainable production of sugarcane. The claim alleged that Bonsucro had failed to comply with the OECD Guidelines because it had not carried out appropriate due diligence towards one of its members, accused of human rights abuses. While NCP complaints had been brought against MSIs and certifiers before, the UK NCP’s final statement is the first to recognize the leverage MSIs have over members due to their ability to deny membership and related reputational benefits to companies wishing to show sustainability logos, and to affirm their responsibility to use this leverage to avoid abuses. The statement sheds light on the accountability of actors involved in private voluntary sustainability standard systems, with possible impacts on other actors such as third-party certifiers.