Which type of lien is placed on property without the consent of the owner?

An involuntary lien is a type of lien imposed on a property without the consent of the property owner. This often occurs because of legal obligations, such as unpaid property taxes, court judgments, or unpaid debts. Since the owner has not agreed to this lien, it can be enforced by the creditor, leading to potential claims against the property, including the possibility of foreclosure to recover the owed amount.

In contrast, voluntary liens, such as mortgages, are agreed to by the property owner in exchange for loans or other benefits. Equitable liens arise from court decisions based on fairness, typically to enforce payment for services rendered or to prevent unjust enrichment. Collateral liens, while not a standard term, generally refer to liens where the property serves as collateral for a specific obligation, usually with the owner's knowledge and consent. Hence, the defining characteristic of an involuntary lien is that it is established without the owner's agreement, making it the correct choice in this scenario.