Whether the landlord's payment notice of 12 August 2009 was sufficiently specific under Art. 257d CO to support termination and eviction.
Yes. The arrears were determinable without ambiguity: the notice identified the outstanding rent for June to August 2009 and the amount claimed corresponded to the remaining balance due.
A notice need not detail every component if the tenant can understand the debt without doubt. Here the omission of the prior partial payment did not create ambiguity, and the tenant could not reasonably have misunderstood the claim.