(1) Where a person has been insured under the legislation of both Parties, the insurance authority in the territory of the Party whose legislation was applicable at the time when incapacity for work followed by invalidity occurred shall determine, in accordance with its legislation, whether the person concerned satisfies the conditions for invalidity pension taking account, where appropriate, both for the determination of entitlement and for the calculation of the pension of any insurance period which that person has completed under the legislation of the other Party as if it were an insurance period completed under its legislation. For the purpose of determining entitlement to a Norwegian invalidity pension, insurance periods under Norwegian legislation must amount to at least one year.
(2) For the purpose of determining entitlement to:
(a)supplementary pension under the legislation of Norway, no account shall be taken of any contribution period completed under the legislation of the United Kingdom;
(b)additional pension payable under the legislation of the United Kingdom, no account will be taken of any contribution period completed under the legislation of Norway.
(3) Where a person would be entitled to receive for the same incapacity and for the same period invalidity pension under the legislation of both Parties, or invalidity pension under the legislation of one Party and sickness benefit under the legislation of the other Party, whether by virtue of this Convention or otherwise, he shall be entitled to receive only the invalidity pension or sickness benefit, as the case may be, payable in accordance with the provisions of paragraph (1) of this Article, under the legislation of the Party in whose territory the incapacity began.
(4) Where the amount of the invalidity pension payable under the legislation of the United Kingdom is less than the amount of benefit which would have been payable under the legislation of Norway but for the provisions of paragraph (3) of this Article, Norway shall also pay its benefit, but the amount of that benefit shall be limited to the amount by which the benefit it would have paid but for the provisions of paragraph (3) would have exceeded the amount of invalidity pension payable under the legislation of the United Kingdom.
(5) With regard to the reduction of the pension point years required for the calculation of a full supplementary pension for persons born before 1937 the requirements concerning periods of residence in Norway laid down in Norwegian legislation shall be applied to persons other than Norwegian nationals. The supplementary pension calculated on the basis of such a reduction shall be payable only to persons present or resident in Norway or in the territory of the United Kingdom.
(6) Where an invalidity pension is payable under the legislation of Norway in conformity with the provisions of this Article to a person who has become entitled to an old age pension under the legislation of the United Kingdom, the periods of insurance taken into account for the calculation of the old age pension of the United Kingdom shall not be taken into account for the calculation of the invalidity pension payable under the legislation of Norway. When a Norwegian old age pension becomes payable, it shall be calculated on the basis of the same periods of insurance as the invalidity pension which was payable under this provision.