Ar cle 306 Where a co-owner by shares transfers the por on of shares he owned in the co-owned immovable or movable property, he shall no fy the other co-owners of the condi ons of transfer in a mely manner. The other co-owners shall exercise their right of pre-emp on within a reasonable period of me. Where two or more co-owners assert their rights of pre-emp on, they shall determine through nego a on the propor on of shares each may purchase; where no agreement is reached, they shall exercise their right of pre-emp on in propor on to the shares they each own at the me of transfer. Ar cle 307 In terms of external rela ons, the co-owners are jointly and severally en tled to claims and are jointly and severally obligated to perform obliga ons arising from the co-owned immovable or movable property, unless it is otherwise provided by law or where the third person is aware that the co-owners are not in a rela onship of joint and several claims and obliga ons. In terms of internal rela ons, unless otherwise agreed by the co-owners, the co-owners by shares are en tled to claims and obligated to perform obliga ons in propor on to the shares they each own, and the joint co-owners are jointly en tled to claims and obligated to perform obliga ons. A co-owner by shares who has performed the obliga on in excess of his shares has the right of contribu on against the other co-owners. Ar cle 308 Where there is no agreement among the co-owners or the agreement is unclear as to whether the co-owned immovable or movable property is under co-ownership by shares or under joint co-ownership, the immovable or movable property shall be deemed to be under co-ownership by shares, unless the coowners are in a rela onship such as familial rela onship and the like. Ar cle 309 The share of a co-owner by shares in the immovable or movable property shall be determined according to his capital contribu on where there is no agreement or the agreement is unclear. Where it is impossible to determine the amount of capital contribu on, each co-owner by shares shall be en tled to an equal share. Ar cle 310 Where two or more organiza ons or individuals are jointly en tled to a right to usufruct or a security interest, the relevant provisions of this Chapter shall be applied muta s mutandis. Chapter IX Special Provisions on the Acquisi on of Ownership Ar cle 311 Where a person with no right to dispose of an immovable or movable property transfers it to another person, the owner has the right to recover it; unless otherwise provided by law, the transferee acquires the ownership of the immovable or movable property under the following circumstances: (1) the transferee is in good faith at the me when the immovable or movable property is transferred to him; (2) the transfer is made at a reasonable price; and (3) the transferred immovable or movable property has been registered as required by law, or has been delivered to the transferee where registra on is not required. Where a transferee acquires the ownership of the immovable or movable property in accordance with the provisions of the preceding paragraph, the original owner has the right to claim damages against the person who disposes of the property without a right. Where a party acquires, in good faith, a real right other than ownership, the provisions of the preceding two paragraphs shall be applied muta s mutandis. Ar cle 312 An owner or any other right holder has the right to recover a lost thing. Where the lost thing is possessed by another person by way of transfer, the right holder has the right to claim damages against the person who disposes of the thing without the right to disposi on, or to request the transferee to return the original thing within two years from the date on which the right holder knows or should have known of the transferee, provided that where the transferee has acquired the lost thing at auc on or from a quali ed business operator, the right holder shall, at the me of reques ng the return of the original thing, reimburse the expenses that have been paid by the transferee. The right holder has, a er having reimbursed the expenses paid by the transferee, the right to indemni ca on against the person who disposes of the thing ti ti ti ti fi ti ti ti ti ti ti ti ti ft ti ti ti ti ti ti ti ti ti ti ti fi ti ti ti ti ti ti ti ti ti ti ti ti ti ti ti ti ti ti ti ti ti ti ti ti ti ti ti 35