BAR by Prior Judgment vs. CONCLUSIVENESS of Judgment

What is the difference between bar and conclusiveness in res judicata?

BAR BY PRIOR JUDGMENT: In other cases, the judgment or final order is, with respect to the matter directly adjudged or as to any other matter that could have been raised in relation thereto, conclusive between the parties and their successors in interest by title subsequent to the commencement of the action or special proceeding, litigating for the same thing and under the same title and in the same capacity;

The judgment or decree of a court of competent jurisdiction concludes the litigation between the parties and their successors or privies and bars a new action or suit involving the same cause of action

CONCLUSIVENESS OF JUDGMENT: In any other litigation between the same parties or their successors in interest, that only is deemed to have been adjudged in a former judgment or final order which appears upon its face to have been so adjudged, or which was actually and necessarily included therein or necessary thereto.

Any right, fact or matter in issue which has been directly adjudicated upon or is necessarily involved in the determination of the action by a competent court is conclusively settled by the judgment or final order and CANNOT be litigated again by the parties and their privies. (G.R. No. 191101; October 1, 2014)
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. In this instance, the judgment in the first case constitutes an absolute bar to the second action. Otherwise put, the judgment or decree of the court of competent jurisdiction on the merits concludes the litigation between the parties, as well as their privies, and constitutes a bar to a new action or suit involving the same cause of action before the same or other tribunal.

But where there is identity of parties 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. This is the concept of res judicata known as "conclusiveness of judgment." Stated differently, any right, fact or matter in issue directly adjudicated or necessarily involved in the determination of an action before a competent court in which judgment is rendered on the merits is conclusively settled by the judgment therein and cannot again be litigated between the parties and their privies whether or not the claim, demand, purpose, or subject matter of the two actions is the same.

For res judicata under the first concept, bar by prior judgment, to apply, the following requisites must concur, viz: (a) finality of the former judgment; (b) the court which rendered it had jurisdiction over the subject matter and the parties; (c) it must bea judgment on the merits; and (d) there must be, between the first and second actions, identity of parties, subject matter and causes of action. (G.R. No. 191101; October 1, 2014)