Short answer. It is placed in judicial deposit. Article 2005 provides that a judicial deposit or sequestration takes place when an attachment or seizure of property in litigation is ordered. The property is held in custody by a court-appointed keeper and preserved intact until the case ends — not handed over to the party who obtained the order.
What the law says
A judicial deposit or sequestration takes place when an attachment or seizure of property in litigation is ordered
Civil Code, Article 2005 — Judicial Deposit (Sequestration). Read the full provision →
Seizure during a case is a custody, not a transfer
When a court orders property attached or seized while a suit is going on, what results is a judicial deposit. Article 2005 puts it plainly: A judicial deposit or sequestration takes place when an attachment or seizure of property in litigation is ordered. Unlike an ordinary deposit, which two people agree to, this one is created by the court's order alone. The party who obtained the order does not take the thing home. It goes into the hands of a keeper answerable to the court, whose whole task is to keep it exactly as it is until the dispute over it is resolved.
Why property is put under custody
Sequestration exists so that a judgment does not arrive too late to matter. If the thing being fought over could be sold, hidden, encumbered or run down while the case dragged on, the eventual winner might be handed nothing but a piece of paper. Placing the property under court custody freezes it in place: it cannot be disposed of, and its condition is preserved. An attachment serves a related purpose where the claim is for money, holding assets so that a money judgment can actually be satisfied out of them rather than defeated by a debtor emptying his hands first.
The property is preserved, not used or disposed
While the thing is sequestered nobody may treat it as his own. The keeper does not use it, lend it, or dispose of it, and he must account for it. He is bound to the care a prudent owner gives his own property, and he cannot walk away from the responsibility while the controversy that put the property in his hands is still alive. That is why the custody typically lasts as long as the litigation does. Perishable or rapidly depreciating property is the usual exception a court has to manage specially, so that preserving the asset does not simply destroy its value.
What it means for the parties
Having property sequestered is not the same as owning it or winning the case. Custody settles nothing about the merits; it only holds the position steady until the court decides who is entitled. If you prevail, the thing is released to you in the condition it was preserved. If you lose, it goes back to the other side. Either way, keep your own record of what was seized and its state at the time — an inventory or photographs at the point of seizure — because a fight over condition or shortage at the end is common and hard to reconstruct afterwards.