Key legal question
Whether Y________ SA had passive standing despite the group confusion between parent and subsidiary
Extracted holding
Yes. Because the group presented an outward unity and the claimant could in good faith address demands to either company, the parent company was passively legitimated.
Extracted reasoning
The companies shared similar names, same seat, analogous business purpose and common representatives. Communications on prescription and the 2008 indemnity claim created an appearance of unity; the claimant could rely on that appearance under the principle of good faith.