1BY A JUDGMENT OF 10 FEBRUARY 1978 WHICH WAS RECEIVED AT THE COURT OF JUSTICE ON 2 MARCH 1978 THE COUR DU TRAVAIL , MONS , PURSUANT TO ARTICLE 177 OF THE EEC TREATY , HAS SUBMITTED TWO QUESTIONS ON THE INTERPRETATION OF ARTICLE 11 OF REGULATION NO 3 OF THE COUNCIL OF 25 SEPTEMBER 1958 ( JOURNAL OFFICIEL 1958 , P . 561 ) AND OF ARTICLE 9 OF REGULATION NO 4 OF THE COUNCIL OF 3 DECEMBER 1958 ( JOURNAL OFFICIEL 1958 , P . 597 ) ON SOCIAL SECURITY FOR MIGRANT WORKERS .
2THE QUESTIONS AROSE IN THE CONTEXT OF A CASE RELATING TO THE CALCULATION BY THE COMPETENT BELGIAN INSTITUTION OF THE INVALIDITY PENSION OF AN ITALIAN NATIONAL , THE PLAINTIFF IN THE MAIN ACTION , WHO HAS WORKED IN ITALY AND IN BELGIUM .
3IN BELGIUM THE WORKER SATISFIED ALL THE CONDITIONS LAID DOWN BY NATIONAL LEGISLATION FOR ACQUISITION OF THE RIGHT TO AN INVALIDITY PENSION UNDER THE COMPULSORY INSURANCE SCHEME AGAINST SICKNESS AND INVALIDITY WITHOUT ITS BEING NECESSARY FOR HIM TO RELY ON PERIODS COMPLETED IN ANOTHER MEMBER STATE .
4ON THE OTHER HAND FOR THE ACQUISITION OF A RIGHT TO BENEFITS IN ITALY HE HAD TO RELY ON THE PROVISIONS OF REGULATION NO 3 AND IN CALCULATING THOSE BENEFITS THE PERIODS ACTUALLY COMPLETED IN THE TWO MEMBER STATES WERE AGGREGATED AND THE ITALIAN BENEFITS WERE APPORTIONED .
5ON BEING INFORMED OF THE AWARD OF APPORTIONED ITALIAN BENEFITS THE BELGIAN INSTITUTION , HAVING REGARD TO THE RULES AGAINST THE AGGREGATION OF BENEFITS CONTAINED IN ARTICLE 70 ( 2 ) OF THE BELGIAN LAW OF 9 AUGUST 1963 ON THE ESTABLISHMENT AND ORGANIZATION OF A SCHEME OF COMPULSORY INSURANCE AGAINST SICKNESS AND INVALIDITY , RAISED THE PROBLEM OF THE OVERLAPPING OF THE BENEFITS .
6ON APPEAL THE CASE WAS BROUGHT BEFORE THE COUR DU TRAVAIL , MONS , WHICH , BY A FIRST JUDGMENT OF 25 JUNE 1976 , RULED THAT MR VIOLA COULD NOT RECEIVE THE BELGIAN BENEFITS FOR INCAPACITY FOR WORK IN ADDITION TO THE INVALIDITY PENSION PAID BY THE ITALIAN AUTHORITIES BUT THAT THE RIGHT TO CLAIM A REFUND OF THE SUMS PAID BEFORE 1 MAY 1969 WAS TIME-BARRED ; IT THEREFORE ORDERED THAT THE PROCEEDINGS BE REOPENED TO ENABLE THE PARTIES TO THE MAIN ACTION TO DETERMINE THE AMOUNT OF THE SUMS PAID TO MR VIOLA BY THE ITALIAN INSTITUTION FROM 1 MAY 1969 TO 30 APRIL 1971 .
7THE JUDGMENT OF 25 JUNE 1976 LEFT UNANSWERED THE QUESTION WHETHER , FOR THE APPLICATION OF THE BELGIAN RULES AGAINST THE OVERLAPPING OF BENEFITS , THE PENSION SUPPLEMENTS FOR A DEPENDENT SPOUSE AND THE ANNUAL SUPPLEMENT AWARDED AT CHRISTMAS TIME , PROVIDED FOR BY THE ITALIAN LEGISLATION , WERE AN INTEGRAL PART OF THE INVALIDITY PENSION AND IN ORDER TO RESOLVE THIS PROBLEM THE COUR DU TRAVAIL , MONS , BY A SECOND JUDGMENT OF 10 FEBRUARY 1978 , REFERRED THE FOLLOWING QUESTIONS TO THE COURT OF JUSTICE FOR A PRELIMINARY RULING :
1 . DOES THE SUPPLEMENTARY ALLOWANCE FOR A DEPENDENT SPOUSE GRANTED BY THE ITALIAN LEGISLATION IN FORCE BETWEEN 1 MAY 1969 AND 30 APRIL 1971 FORM AN INTEGRAL PART OF THE ITALIAN INVALIDITY PENSION FOR THE PURPOSE OF APPLYING THE RULES ABOUT OVERLAPPING BENEFITS LAID DOWN IN ARTICLE 11 OF REGULATION NO 3 AND ARTICLE 9 OF REGULATION NO 4?
2 . SHOULD THE PAYMENT OF A ' ' 13TH MONTH ' ' MADE TO THE RESPONDENT BY THE INPS IN 1969 AND 1970 , UNDER THE ITALIAN LEGISLATION OF 4 APRIL 1952 , BE TREATED AS PART OF THE PENSION FOR THE PURPOSE OF APPLYING THE RULES ABOUT OVERLAPPING BENEFITS LAID DOWN IN EUROPEAN REGULATIONS NO 3 AND NO 4?
8ACCORDING TO ARTICLE 26 OF REGULATION NO 3 , ARTICLES 27 AND 28 RELATING TO OLD-AGE AND DEATH PENSIONS SHALL APPLY BY ANALOGY TO THE PAYMENT OF INVALIDITY BENEFITS WHEN THE INSURED HAS COMPLETED PERIODS UNDER DIFFERENT LEGISLATIVE SYSTEMS OF WHICH AT LEAST ONE IS OF TYPE B .
9THE REGULATIONS IN THE FIELD OF SOCIAL SECURITY HAVE AS THEIR BASIS , THEIR FRAMEWORK AND THEIR BOUNDS ARTICLES 48 TO 51 OF THE TREATY , WHICH ARE INTENDED TO SECURE FREEDOM OF MOVEMENT FOR WORKERS .
10FROM THIS POINT OF VIEW , ARTICLE 51 OF THE TREATY AND ARTICLE 27 OF REGULATION NO 3 REFER ABOVE ALL TO CASES IN WHICH THE LEGISLATION OF ONE MEMBER STATE BY ITSELF WOULD NOT ENABLE AN INSURED PERSON TO QUALIFY FOR THE RIGHT TO BENEFIT BECAUSE OF AN INSUFFICIENT NUMBER OF PERIODS COMPLETED UNDER THAT LEGISLATION .
11TO REMEDY THE SITUATION THESE PROVISIONS PROVIDE , FOR THE BENEFIT OF A WORKER WHO HAS BEEN SUCCESSIVELY OR ALTERNATELY SUBJECT TO THE LEGISLATION OF TWO OR MORE MEMBER STATES , FOR THE AGGREGATION OF INSURANCE PERIODS COMPLETED UNDER THE LEGISLATION OF EACH OF THOSE STATES .
12AS REGARDS OLD-AGE AND DEATH PENSIONS , ARTICLES 27 AND 28 OF REGULATION NO 3 APPLY TO SUCH A SITUATION , BUT NOT WHEN IN A STATE THE OBJECT SOUGHT BY ARTICLE 51 IS ATTAINED UNDER NATIONAL LEGISLATION ALONE .
13THE SCHEME OF ARTICLES 27 AND 28 THUS IMPLIES A SIMULTANEOUS APPLICATION OF THOSE TWO PROVISIONS .
14AS A RESULT , APPORTIONEMENT OF BENEFITS MAY NOT BE MADE , UNLESS IT HAS BEEN NECESSARY , FOR THE ACQUISITION OF THE RIGHT , TO AGGREGATE BEFOREHAND THE PERIODS COMPLETED UNDER DIFFERENT LEGISLATIVE SYSTEMS , BUT IT MAY NOT BE USED IF ITS EFFECT IS TO REDUCE THE BENEFITS WHICH THE INSURED PERSON CAN CLAIM UNDER THE LEGISLATION OF A SINGLE STATE .
15THE SAME CONSIDERATIONS REQUIRE THE APPLICATION OF THE SAME RULES WHEN THE PROBLEM ARISES OF THE APPLICATION BY ANALOGY OF ARTICLES 27 AND 28 TO INVALIDITY PENSIONS .
16AS THE COURT OF JUSTICE HAS ALREADY RULED IN ITS JUDGMENT OF 14 MARCH 1978 IN CASE 83/77 ( NASELLI V CAISSE AUXILIAIRE D ' ASSURANCE MALADIE-INVALIDITE ( 1978 ) ECR 683 ) THE RESTRICTIONS REFERRED TO IN ARTICLE 11 ( 2 ) OF THE REGULATION APPLY TO INSURED PERSONS ONLY AS REGARDS BENEFITS ACQUIRED BY APPLYING REGULATIONS NOS 3 AND 4 .
17ON THE OTHER HAND CONSIDERATION OF THE OTHER PROVISIONS OF REGULATION NO 3 SHOWS THAT NONE OF THEM PRECLUDES THE APPLICATION TO BENEFITS ACQUIRED BY VIRTUE OF NATIONAL LEGISLATION ALONE OF NATIONAL RULES AGAINST THE OVERLAPPING OF BENEFITS .
18CONSEQUENTLY IN A CASE SUCH AS THIS WHERE THE INSURED IS ENTITLED TO A PENSION BY VIRTUE OF THE PROVISIONS OF HIS NATIONAL LEGISLATION ALONE , THE NATIONAL RULES AGAINST THE OVERLAPPING OF BENEFITS ARE APPLICABLE TO HIM .
19IN APPLYING THE RULES AGAINST THE OVERLAPPING OF BENEFITS , IT IS FOR THE NATIONAL COURT TO CLASSIFY THE BENEFITS REFERRED TO IN THE QUESTIONS RAISED , IN CONFORMITY WITH THE APPLICABLE NATIONAL LEGISLATION TAKING ACCOUNT OF THE RULES RELATING TO THE CONFLICT OF LAWS AND THE COMMUNITY PROVISIONS ARE NOT RELEVANT .
20HOWEVER , IN ORDER TO ENSURE THAT A MIGRANT WORKER DOES NOT LOSE THE BENEFIT OF A PENSION TO WHICH HE WOULD BE ENTITLED UNDER THE RULES OF NATIONAL LEGISLATION ALONE THE COURT OF JUSTICE IN THE MANCUSO CASE ( CASE 140/73 SECURITE SOCIALE PARIS V MANCUSO ( 1973 ) 2 ECR 1449 ) HELD THAT IN CERTAIN CASES THE RULES CONCERNING AGGREGATION AND APPORTIONMENT ARE NOT APPLICABLE .
21ACCORDINGLY IF THE PROVISIONS OF NATIONAL LEGISLATION ALONE , INCLUDING THE RULES AGAINST THE AGGREGATION OF BENEFITS , ARE LESS FAVOURABLE TO THE INSURED PERSON THAN THE RULES RELATING TO AGGREGATION AND APPORTIONMENT , IT IS THE LATTER RULES WHICH SHOULD BE APPLIED .
COSTS
22THE COSTS INCURRED BY THE BELGIAN GOVERNMENT AND BY THE COMMISSION OF THE EUROPEAN COMMUNITIES , WHICH HAVE SUBMITTED OBSERVATIONS TO THE COURT , ARE NOT RECOVERABLE .
23AS THESE PROCEEDINGS ARE , IN SO FAR AS THE PARTIES TO THE MAIN ACTION ARE CONCERNED , IN THE NATURE OF A STEP IN THE ACTION PENDING BEFORE THE NATIONAL COURT , THE DECISION ON COSTS IS A MATTER FOR THAT COURT .
ON THOSE GROUNDS ,
THE COURT
IN ANSWER TO THE QUESTIONS REFERRED TO IT BY THE COURT DU TRAVAIL , MONS , BY JUDGMENT OF 10 FEBRUARY 1978 , HEREBY RULES :
1 . IN APPLYING THE NATIONAL RULES AGAINST THE OVERLAPPING OF BENEFITS , IT IS FOR THE NATIONAL COURT TO CLASSIFY THE SUPPLEMENT FOR A DEPENDENT SPOUSE AND THE ' ' 13TH MONTH ' ' IN ACCORDANCE WITH THE APPLICABLE NATIONAL LEGISLATION , REGARD BEING HAD TO THE RULES RELATING TO CONFLICT OF LAWS SINCE THE COMMUNITY PROVISIONS ARE NOT RELEVANT .
2 . HOWEVER , IF THE APPLICATION OF THE RELEVANT NATIONAL LEGISLATION IS LESS FAVOURABLE THAN THAT OF THE SYSTEM OF AGGREGATION AND APPORTIONMENT , THE LATTER SYSTEM MUST BE APPLIED .