Key legal question
Whether a modification of interim maintenance measures under Art. 145 ZGB may be made retroactive beyond the filing date of the request.
Extracted holding
As a rule, modification takes effect only from the filing date; further retroactivity requires special circumstances.
Extracted reasoning
The parties must be able to rely on the provisional measure until it is challenged. Greater retroactivity is exceptional and requires special reasons such as an objectively justified or culpably caused inability to clarify finances.