Questão jurídica principal
Whether the appellant could exercise the option right alone under the 1997 authentic deed.
Decisão extraída
No. The contract was interpreted as allowing only joint exercise of the option right.
Fundamentação extraída
The cantonal court's finding of the parties' actual common intent could not be disturbed. The deed was not incomplete, and the court properly refused to infer a unilateral exercise right or apply accession by analogy.