This report analyzes the legal feasibility of financing mechanisms for PtX CfD windows under three key frameworks: European State aid law, the EU Foreign Subsidies Regulation, and WTO law. Under State aid law, financial contributions to PtX CfD windows may qualify as State aid, requiring compatibility with internal market rules based on the Guidelines on Climate, Environmental Protection, and Energy Aid. The EU Foreign Subsidies Regulation introduces notification requirements for third-country subsidies, impacting both PtX intermediaries and contractors. WTO law assesses subsidies based on the Agreement on Subsidies and Countervailing Measures (ASCM), distinguishing permissible, actionable, and prohibited subsidies, with export subsidies being particularly scrutinized.