Facts
The appellant [X.] and the respondent [Y.] jointly acquired the company [S. AG] and its affiliated companies in 2005. Subsequently, they became involved in a conflict, which they sought to resolve with a "Disentanglement Agreement" dated June 12, 2008. It was agreed that [X.] would retroactively as of December 31, 2007 sell his 245 registered shares of [T. AG] to [Y.] for CHF 60 million, with the purchase price to be settled by offsetting counterclaims and granting a loan of CHF 45,509,490. Since [Y.] did not pay the remaining amount of CHF 43,509,490, [X.] initiated debt collection proceedings No. ... with the Debt Collection Office [A.] and applied for provisional enforcement. The Cantonal Court of Graubünden dismissed [X.] 's appeal against the rejection of the provisional enforcement.
Considerations
The Federal Supreme Court overturns the decision of the Cantonal Court and grants [X.] provisional enforcement in debt collection proceedings No. ... of the Debt Collection Office [A.] for CHF 43,509,490 plus 6% interest since June 12, 2008. It justifies this as follows:
The Disentanglement Agreement is not a bilateral, but a multilateral contract with 16 participating parties. However, the contractual part in which [X.] sells 245 registered shares of [T. AG] to [Y.] for CHF 60 million is synallagmatic. Since the sold shares have been transferred, there is a debt acknowledgment within the meaning of Art. 82 para. 1 DEBA. The return of the…