Organisation for Economic Cooperation & Development (OECD)+Minerals Policy Alignment - Downstream Companies (Step 1.C.3.5)+methodology
This information is typically mentioned in the company's minerals sourcing policy, but could also be found in documents like Sustainability or Annual Reports.
For more details on alignment to the OECD Guidance, see Section C.5.1 and C.5.3 of the Guidance (page 39) here