See - https://www.lawphil.net/judjuris/juri2013/jul2013/am_ca-13-51-j_2013.html
"x x x.
In the appellate stage, therefore, the rigid policy is to make the consolidation of all cases and proceedings resting on the same set of facts, or involving identical claims or interests or parties mandatory. Such consolidation should be made regardless of whether or not the parties or any of them requests it. A mandatory policy eliminates conflicting results concerning similar or like issues between the same parties or interests even as it enhances the administration of justice.
In this connection, the Court reminds all attorneys appearing as counsel for the initiating parties of their direct responsibility to give prompt notice of any related cases pending in the courts, and to move for the consolidation of such related cases in the proper courts. This responsibility proceeds from their express undertakings in the certifications against forum-shopping that accompany their initiatory pleadings pursuant to Section 5 of Rule 7 and related rules in the Rules of Court, to the effect that they have not theretofore commenced any actions or filed any claims involving the same issues in any court, tribunal or quasi-judicial agency and, to the best of their knowledge, no such other actions or claims are pending therein; that if there were such other pending actions or claims, to render complete statements of the present status thereof; and if they should thereafter learn that the same or similar actions or claims have been filed or are pending, they shall report that fact within five days therefrom to the courts wherein the said complaints or initiatory pleadings have been filed.
WHEREFORE, the Court DISMISSES the administrative complaint against Presiding Justice Andres B. Reyes, Jr., Associate Justice Isaias P. Dicdican and Associate Justice Stephen C. Cruz of the Court of Appeals for its lack of merit.
The Court of Appeals is DIRECTED to forthwith adopt measures that will ensure the strict observance of Section 3, Rule III of the 2009 Internal Rules of the Court of Appeals, including the revision of the rule itself to make the consolidation of cases and proceedings concerning similar or like issues or involving the same parties or interests mandatory and not dependent on the initiative of the parties or of any of them.
All attorneys of the parties in cases brought to the third level courts either on appeal or interlocutory review (like certiorari) are REQUIRED to promptly notify the reviewing courts of the pendency of any other cases and proceedings involving the same parties and issues pending in the same or other courts.
Let this decision be FURNISHED to the Court of Appeals, Sandiganbayan, Court of Tax Appeals and the Office of the Court Administrator for their guidance; and to the Integrated Bar of the Philippines for dissemination to all its chapters.
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