NATIONAL D ' ASSURANCE MALADIE-INVALIDITE ( NATIONAL SICKNESS AND INVALIDITY INSURANCE INSTITUTION ), A BELGIAN SOCIAL SECURITY INSTITUTION ( HEREINAFTER REFERRED TO AS ' ' THE BELGIAN INSTITUTION ' ' ), TO REFUSE TO GRANT HIM THE PROPORTIONAL BELGIAN INVALIDITY PENSION .
3 MR KNOELLER WAS INCAPABLE OF WORKING AS FROM 18 AUGUST 1967 BUT IT WAS ONLY WITH EFFECT FROM 1 DECEMBER 1967 THAT AN INVALIDITY PENSION WAS GRANTED TO HIM , UPON HIS APPLICATION , BY THE LANDESVERSICHERUNGSANSTALT RHEINPROVINZ ( REGIONAL INSURANCE INSTITUTION FOR THE RHINE PROVINCE ), HEREINAFTER REFERRED TO AS ' ' THE GERMAN INSTITUTION ' ' . IN THE MEANTIME , HE WAS , NEVERTHELESS , IN RECEIPT OF UNEMPLOYMENT BENEFITS IN THE FEDERAL REPUBLIC OF GERMANY . UNDER GERMAN LAW THAT INTERVAL IN NO WAY AFFECTS ENTITLEMENT TO THE INVALIDITY PENSION AND WAS THEREFORE NOT MENTIONED ON FORM E 26 WHICH WAS FORWARDED BY THE GERMAN INSTITUTION TO THE BELGIAN INSTITUTION SO AS TO ENABLE MR KNOELLER TO ACQUIRE A RIGHT TO A BELGIAN INVALIDITY PENSION PROPORTIONATE TO THE PERIOD OF EMPLOYMENT COMPLETED BY HIM IN BELGIUM . FOR THE REASON GIVEN ABOVE , THAT FORM MERELY MENTIONS PERIODS OF INSURANCE COMPLETED BY MR KNOELLER UNTIL 18 AUGUST 1967 , THAT IS TO SAY UNTIL THE DATE OF TERMINATION OF HIS EMPLOYMENT .
4 HAVING REGARD TO THE FACT THAT UNDER BELGIAN LAW A WORKER IS NOT ENTITLED TO AN INVALIDITY PENSION IF HE HAS NOT COMPLETED 120 DAYS OF WORK OR DAYS ASSIMILATED THERETO ( SUCH AS PERIODS OF REGISTERED UNEMPLOYMENT ) DURING THE SIX MONTHS PRECEDING THE CESSATION OF WORK , THE BELGIAN INSTITUTION IN THE PRESENT CASE CONSIDERED THAT , ON THE BASIS OF THE INFORMATION CONTAINED IN FORM E 26 , THAT CONDITION HAD NOT BEEN SATISFIED . IN FACT , THE BELGIAN INSTITUTION TOOK THE VIEW THAT THE INFORMATION GIVEN COULD NOT BE AMENDED OR SUPPLEMENTED BY THE LETTERS OF 5 AND 21 MARCH 1970 FROM THE GERMAN INSTITUTION IN WHICH IT WAS EXPLAINED THAT DURING THE PERIOD OF UNEMPLOYMENT MR KNOELLER WAS LEGALLY ' ' INSURED ' ' UNDER GERMAN LAW .
5 FOLLOWING MR KNOELLER ' S COMPLAINT , BOTH THE TRIBUNAL DU TRAVAIL ( LABOUR COURT ), VERVIERS , AND THE COUR D ' APPEL ( COURT OF APPEAL ), LIEGE , RULED THAT THE CLAIMANT WAS ENTITLED TO THE PROPORTIONAL BELGIAN INVALIDITY PENSION . THE BELGIAN INSTITUTION APPEALED ON A POINT OF LAW AGAINST THE JUDGMENT OF THE COUR D ' APPEL , LIEGE , AND THE BELGIAN COUR DE CASSATION BY JUDGMENT OF 6 APRIL 1981 , DECIDED TO STAY THE PROCEEDINGS AND TO REFER THE FOLLOWING QUESTION TO THE COURT OF JUSTICE :
' ' TO DETERMINE THE PROPORTIONAL INVALIDITY PENSION DUE TO A WORKER FOR WORK DONE IN BELGIUM MUST REFERENCE BE MADE ONLY TO THE INFORMATION CONTAINED IN FORM E 26 PROVIDED FOR BY ARTICLE 34 OF REGULATION NO 4 OF THE COUNCIL OF THE EUROPEAN ECONOMIC COMMUNITY OF 3 DECEMBER