For a company to be a leader and fully comply with GRI, it need to have a public GRI index, report material topics requirements aligned with its own materiality assessment and fully comply with these requirements (either within the core or comprehensive option) or have understandable reason for omission.
For a company to comply with GRI, it need all the above but may have reason for omission such as ‘information not available’ in it’s GRI index.
If a company does not have a public GRI index, GRI topics not aligned with its own materiality assessment, inaccurate GRI index or disclosure not compliant with GRI requirements it will be assessed as not compliant.

For a company to comply with SASB it needs to report all information associated with its associated industry standard (as indicated on SASB website) with none or reasonable methodology modification.
If a company does not comply with all SASB requirement or apply significant modification to the SASB methodology it will be assessed as not compliant.

For a company to be a leader and fully comply with TCFD it needs to report all core recommendations, recommended disclosures, guidance for all sectors, supplemental guidance for certain sectors and associated illustrative metrics.
For a company to  comply with TCFD it needs to report all core recommendations and recommended disclosures in its financial filings.
If a company does not comply with all TCFD core recommendations and recommended disclosures or if they are not in its financial filings it will be assessed as not compliant.