The Supreme Court once held that "when a registration has been transferred successively without cause, the true owner who wants to restore his name as owner may perhaps demand cancellation of that registration from the registered holder, but cannot demand performance of a transfer registration on the ground of recovery of ownership" (Supreme Court Decision 72Da1846, 1847, December 26, 1972). Later, however, the Court held: "A person who already had a registration showing ownership in his name, or who acquired ownership by law, should be allowed, as a way to restore the true registered title, not only to seek cancellation of the registration from the current registered holder but also to seek directly performance of a transfer registration on the ground of restoring true title. This is because the purpose of the real estate registration system in trying to show the course of real rights changes as it occurred is ultimately to exclude registrations that do not match the facts and to publicly show the present state of rights as legitimate, thereby promoting the safety of real estate transactions, and the current false registered holder has a duty to cooperate in publicly showing the true owner; whether he cooperates in restoring the true registered title by cancelling his own registration or by directly transferring it to the true holder, there is no essential difference, and either way he loses his registration and his interests are the same. Accordingly, the decisions to the contrary, including Decision 72Da1846, 1847 of December 26, 1972 and Decision 78Da1916 of January 13, 1981, are overruled."

The Supreme Court has held that "even where the consent of a third party with an interest on the register is required in the procedure for registration of restoration after cancellation, unless that third party has a substantive legal duty to consent in relation to the person entitled to registration, he has no reason to comply with the request for consent" (see Supreme Court Decision 78Da2040, November 13, 1979, and Decision 85Daka2203, May 26, 1987).

When the actual legal relationship and the registration do not match because of forged documents, the substantive owner A can exercise a claim for cancellation of registration as a real-right claim. However, when cancellation is applied for, Article 57(1) of the Real Estate Registration Act requires the consent of any third party with an interest on the register in that cancellation. Therefore A must obtain the consent of C, who registered a mortgage on the register in B's name, to seek cancellation against B. However, C need not give consent unless he has a substantive legal duty to give it to A, the person entitled to registration.

If A does not seek cancellation but instead seeks a transfer registration to restore true title, A can seek a transfer registration from B's name to his own regardless of C's consent. In that case C's mortgage remains and is carried over to A's title.

To add: the precedent that allowed a claim for transfer registration on the ground of restoring true title is Supreme Court En Banc Decision 89Daka12398 of November 27, 1990. Article 621 of the Civil Act, which the paper cites as the basis for registration claims, is the provision on a lessee's right to demand registration of a lease, and there is no single article governing registration claims in general. A forged registration is void, and because Korean law does not give registrations public faith, C, who took a mortgage relying on it, is in principle not protected either. The Real Estate Registration Act was fully revised in 2011, and the paper follows the article numbers after the revision.