Transferring ownership over thing sold

The seller must transfer ownership to the buyer (Art. 1458) and, therefore, the seller must be the owner of the subject bought. In short, nobody can dispose of that which does not belong to him –– nemo dat quad non habet. (See Azcona v. Reyes & Larracas, 59 Phil. 446; see Coronel v. Ona, 33 Phil. 456) It must be recalled, however, the seller need not be the owner at the time of the perfection of the contract.

It is sufficient that he is the owner at the time the object is delivered; otherwise, he may be held liable for breach of warranty against eviction. It is important to take note that the contract of sale by itself is not a mode of acquiring ownership; it is the transfer or "tradition." (Article 712, Civil Code) The contract transfers no real rights; it merely causes certain obligations to arise. Hence, it would seem that A can sell to B property belonging to C at the time of the meeting of the minds. (TS, Jan. 31, 1921) Of course, if at the time A is supposed to deliver, he cannot do so, he has to answer for damages. Having assumed the risk of acquiring ownership from C, it is clear he must be liable in case of failure. (Paras, citing Martin v. Reyes, et al., 91 Phil. 666)

That the seller need not be the owner at the time of perfection is bolstered by the fact that, under the law on sales, "future things or goods" may be the object of sale. While, however, there can be a sale of future property, there can generally be no donation of future property. (Article 751, Civil Code)

A person who has a right over a thing (although he is not the owner of the thing itself) may sell such right. (10 Manresa, p. 25) Hence, a usufructuary may generally sell his usufructuary right. A mortgagor may sell her right of redemption.