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G was the owner of a lot together with the improvements thereon; in 19?? she and respondent R lived together as husband and wife without the benefit of marriage; in September 1982, solely out of love and affection for R, she executed a deed of absolute sale over the said lot in favor of R without any monetary consideration; thereafter, R registered the document in his favor and used the property as collateral for a bank loan of P359900. Subsequently, to protect her interest, she executed an Afdavit of Adverse claim which she filed with the Register of Deeds asserting that her sale in favor of R was null and void for lack of consideration and being contrary to law and public policy. On February 22, 1990, she filed a complaint against R for guieting of title, declaration of nullity of documents and damages. Denying G's claim, R claimed that he was already the registered owner of the property, having acquired the same from G through a notarized deed of absolute sale; the sale was for a valuable consideration and not tainted with fraud nor executed under duress; and, G was estopped from impugning the validity of the sale and questioning his title over the property. On lvlay 22, 1991], the Register of Deeds filed a manifestation informing the trial court that the property had been sold by R to M who was already the registered owner thereof. On September 24, 1990, responding to the amended complaint, M answered that there was no privity of contract between him and G; M was a purchaser for value in good faith; the sale between him and R was executed on 22 December 1989 or long before the execution of the Affidavit of adverse claim. (3 insists that she and R were commonlaw husband and wife, the sale between them was void and inexistent, citing article 1490 of the Civil Code. 1. Is the sale between G and R valid? 2. Is the sale between R and M valid