1 . SOCIAL SECURITY FOR MIGRANT WORKERS - ' PRESENT OR FUTURE ' NATIONAL RULES WITHIN THE MEANING OF ARTICLE 1 ( J ) OF REGULATION NO 1408/71 - CONCEPT - PROVISIONS IN FORCE BEFORE THE ADOPTION OF THE COMMUNITY REGULATIONS - EXCLUSION NOT PERMISSIBLE 2 . SOCIAL SECURITY FOR MIGRANT WORKERS - INVALIDITY INSURANCE - PERIODS OF INSURANCE COMPLETED - LEGISLATION IN FORCE AT THE TIME WHEN THE WORKER WAS EMPLOYED - CESSATION BEFORE THE ADOPTION OF THE COMMUNITY RULES - DIFFERENT LEGISLATION IN FORCE AT THE TIME WHEN THE RISK MATERIALIZES - RIGHT TO BENEFITS ( REGULATION NO 1408/71 OF THE COUNCIL , ARTICLE 40 , ARTICLE 45 ( 3 ))