This document summarizes Rule 45 of the Revised Rules of Procedure Annotated regarding appeals by certiorari. It outlines where petitions for review on certiorari must be filed, which are the Supreme Court. It can be filed from judgments of the Court of Appeals, Sandiganbayan, Regional Trial Courts, and other courts authorized by law. The petition must raise only questions of law. It also lists several exceptions to the general rule that appeals by certiorari are limited to errors of law. It distinguishes petitions for certiorari filed under Rule 45 versus those filed under Rule 65. It provides guidelines on the timing of filing a petition for review on certiorari and consequences for not meeting deadlines.