In principle, a two-person partnership under the Civil Code (Gesellschaft bürgerlichen Rechts) will be dissolved if one of the partners exits the partnership.
If the articles of association provide for the partnership‘s continuation, however, then each of the two partners – by analogous application of Section 737 paragraph 1 of the Bürgerliches Gesetzbuch (BGB, German Civil Code) and Section 140 paragraph 1 sentence 2 of the Handelsgesetzbuch (HGB, German Commercial Code) – will have the right to take over the other partner’s share of the partnership. This right can be exercised by making a corresponding, unilateral declaration towards the other partner. The circumstances of the individual case will determine whether or not valid notice of termination for grave cause can be given to the other partner. However, the parameters for defining “grave cause” are extremely strict in this case.
Source: Ruling of the Oberlandesgericht (OLG, Higher Regional Court) of Koblenz dated July 15th, 2014, 3 U 1462/12.