1 . ECSC - PRODUCTION - SYSTEM OF QUOTAS - OBLIGATION OF THE COMMISSION TO CARRY OUT STUDIES JOINTLY WITH UNDERTAKINGS AND ASSOCIATIONS OF UNDERTAKINGS - LIMITS ( ECSC TREATY , ART . 58 ( 2 )) 2 . ECSC - PRODUCTION - SYSTEM OF QUOTAS - EXISTENCE OF A MANIFEST CRISIS - EXPRESS FINDING FOR EACH SECTOR OF THE STEEL INDUSTRY - NOT REQUIRED ( ECSC TREATY , ART . 58 ( 1 )) 3 . ECSC - PRODUCTION - SYSTEM OF QUOTAS - INSUFFICIENCY OF THE MEANS OF ACTION PROVIDED FOR IN ARTICLE 57 OF THE TREATY - POWER OF APPRAISAL OF THE COMMISSION ( ECSC TREATY , ARTS . 57 AND 58 ( 1 )) 4 . ECSC - PRODUCTION - SYSTEM OF PRODUCTION QUOTAS FOR STEEL - DECISION NO 2794/80 - RETROACTIVE NATURE 5 . MEASURES OF THE INSTITUTIONS - TIME FROM WHICH THEY TAKE EFFECT - PRINCIPLE THAT THEY MAY NOT BE RETROACTIVE - EXCEPTIONS - CONDITIONS 6 . ECSC - OBJECTIVES - COMPROMISE BETWEEN VARIOUS OBJECTIVES - DUTY OF THE COMMISSION ( ECSC TREATY , ARTS . 2 , 3 , AND 4 ) 7 . ECSC - PRODUCTION - SYSTEM OF QUOTAS - CONCOMITANT ADOPTION OF MEASURES CONCERNING IMPORTS FROM NON-MEMBER COUNTRIES - POWER OF APPRAISAL OF THE COMMISSION ( ECSC TREATY , ART . 58 ( 1 )) 8 . ECSC - PRODUCTION - SYSTEM OF PRODUCTION QUOTAS FOR STEEL - DISTINCTION BETWEEN INTEGRATED AND NON-INTEGRATED UNDERTAKINGS - NOT PERMISSIBLE ( ECSC TREATY , ART . 58 ) 9 . ECSC - PRODUCTION - SYSTEM OF PRODUCTION QUOTAS FOR STEEL - PRINCIPLE OF SOLIDARITY - EXCLUSION FROM THE SYSTEM OF SMALL AND MEDIUM-SCALE UNDERTAKINGS - NOT PERMISSIBLE ( ECSC TREATY - ART . 58 ; DECISION NO 2794/80 )