1 . COMMUNITY LAW - GENERAL PRINCIPLES OF LAW - PROPORTIONALITY - DUTIES OF INSTITUTIONS - SCOPE 2 . ECSC - PRICES - COMPULSORY MINIMUM PRICES FOR TRANSACTIONS EFFECTED AS FROM A CERTAIN DATE - TRANSACTIONS ' ' EFFECTED ' ' - CONCEPT ( GENERAL DECISION NO 962/77/ECSC , ART . 2 ) 3 . ECSC - PRICES - MINIMUM PRICES SYSTEM - PRACTICES LEADING TO ACTUAL PRICES LOWER THAN THE MINIMUM PRICES - NOT PERMISSIBLE ( GENERAL DECISION NO 962/77/ECSC )