If downstream developers have direct access to the GPAI model, they can use a wide range of methods to interrogate that model, including creating model-specific metrics, using other AI models to test the GPAI model (called red-teaming or adversarial training), cutting away parts of the model (called pruning), or altering the model in almost any way. Even if the possibilities to update or adapt the models are later expanded, since GPAI models accessed via APIs charge by the amount of data, this strongly discourages the data-intensive process of extensive and routine testing of GPAI models. There is a compelling case that encouraging GPAI developers to sell or lease the GPAI model to downstream developers will lead to better uses of these models.