Clause 58 is one of the package of amendments with regard to the support for Canadian journalism that ensures that the rules work appropriately. In particular, it allows the Canada Revenue Agency to provide the names of organizations that are qualified for the digital news subscription tax credit, so if somebody wants to know if the periodical that they want to subscribe to qualifies for the credit, then the Canada Revenue Agency would be able to provide that information.
On May 27th, 2021. See this statement in context.