When managing an Assay Stream, users can propagate sharing permissions to all assays contained in that stream via a checkbox. This applies the permissions of the Stream to all existing assays; it has no impact on newly created assays (i.e. when creating a new assay, there will not be a message box asking to apply permissions of the stream to the new assay; as is the case with project permissions). This is currently not documented.
Relates to seek4science/seek#2429