RES JUDICATA:

     For the preclusive effect of res judicata to be enforced, the following requisites must be present: (1) the judgment or order sought to bar the new action must be final; (2) the decision must have been rendered by a court having jurisdiction over the subject matter and the parties; (3) the disposition of the first case must be a judgment on the merits; and (4) there must be between the first and second action, identity of parties, subject matter and causes of action. As to the fourth element, it is important to note that the doctrine of res judicata has two aspects: first, “bar by prior judgment” which is provided in Rule 39, Section 47 (b) of the Rules of Court and second, “conclusiveness of judgment” which is provided in Section 47 (c) of the same Rule.  There is “bar by prior judgment” when, as between the first case where the judgment was rendered, and the second case that is sought to be barred, there is identity of parties, subject matter, and causes of action. But where there is identity of parties and subject matter in the first and second cases, but no identity of causes of action, the first judgment is conclusive only as to those matters actually and directly controverted and determined and not as to matters merely involved therein. On the other hand, under the doctrine of conclusiveness of judgment, facts and issues actually and directly resolved in a former suit cannot again be raised in any future case between the same parties, even if the latter suit may involve a different claim or cause of action. The identity of causes of action is not required but merely identity of issues. (PHILIPPINE NATIONAL BANK vs. SIA, G.R. No. 165836, February 18, 2009, Second Division, Quisumbing, J.).