(1) A member shall lose his or her membership of the German Bundestag
1. if the attainment of membership is invalid,
2. if the election result is newly established,
3. if he or she fails to meet one of the prerequisites for permanent eligibility for elec-tion,
4. if he or she resigns,
5. if the Federal Constitutional Court finds, in accordance with Article 21 paragraph (2), second sentence, of the Basic Law, that the party or party branch of which the member has membership is unconstitutional.
Any grounds for loss of membership as laid down in other statutory provisions shall not be affected.
(2) A member whose election in the constituency is invalid shall nevertheless retain his or her membership of the German Bundestag if he or she was at the same time elec-ted on a Land list but was disregarded pursuant to Section 6 subsection (6), fifth sen-tence.
(3) Resignation shall only be effective if it is declared in writing to the President of the German Bundestag, to a German notary whose seat is within the area of application of this Law, or to a member of a German mission abroad who is authorized to authenticate documents. The member must transmit the declaration of resignation attested by a nota-ry or presented to a mission abroad to the President of the Bundestag. The resignation shall be irrevocable.
(4) If a party or party branch is declared unconstitutional by the Federal Constitutional Court in accordance with Article 21 paragraph (2), second sentence, of the Basic Law, the members shall lose their membership of the German Bundestag, and their successors on the list shall lose their candidacy if they have been members of that party or party branch during the period between the filing of the application (Section 43 of the Federal Consti-tutional Court Act) and the pronouncement of the decision (Section 46 of the Federal Constitutional Court Act). If members who have lost their membership in accordance with thr first sentence above have been elected in constituencies, the election of a consti-tuency member shall be repeated in such constituencies, with Section 44 subsections (2) to (4) applicable as appropriate; in these cases, the members who have lost their membership in accordance with the first sentence above shall not be allowed to stand as a candidate. If members who have lost their membership in accordance with the first sentence above have been elected on the basis of a Land list of the party or party branch declared unconstitutional, their seats shall remain vacant. Otherwise, Section 48 sub-section (1) shall apply.