This law amends the definitions in Iceland's Financial Undertakings Act to align with European regulations (CRR III). Key changes include clearer definitions of financial holding companies, ancillary services undertakings, and financial institutions, with specific criteria for when companies fall under each category. The Financial Supervisory Authority is granted authority to assess whether a company qualifies as a financial holding company based on actual activities and risks, in consultation with the European Banking Authority. The law affects financial undertakings, financial institutions, and related companies operating in the financial market.