G.R. No. 259282 - Prieto vs. Bank of the Philippine Islands

Far East Bank and Trust Company (FEBTC) granted several loans to Spouses Antonio and Monette Prieto, evidenced by multiple promissory notes dated between 1996 and 1997, with varying amounts totaling several million pesos.
To secure these loans, petitioners executed real estate mortgages over two registered properties under Transfer Certificate of Title (TCT) Nos. 13062 and 40223.

On June 18, 2002, Bank of the Philippine Islands (BPI), as successor-in-interest of FEBTC, filed a Complaint for sum of money against petitioners for alleged deficiency in their loan obligations.
BPI alleged petitioners’ failure to pay the loans upon maturity, leading to extrajudicial foreclosure of the mortgaged properties.
Public auctions were held on November 10, 1997, and April 23, 2001, with BPI as the highest bidder, but a deficiency balance of P13,268,303.02 remained.
BPI demanded payment of the deficiency, incurred attorney’s fees, and sought judgment against petitioners.

The RTC issued summons, which was lost, issuing an alias summons served on petitioners in 2005.
BPI was substituted by Philippine Asset Investments, Inc. (SPV-AMC), and later by Philippine Investment One [SPV-AMC], Inc.
Petitioners were declared in default in 2005, and the case was archived temporarily due to difficulties in collating evidence.

The RTC initially dismissed the case for lack of interest to prosecute in 2016 but reversed the dismissal following a motion for reconsideration by SPV-AMC, Inc.
SPV-AMC, Inc. presented evidence including promissory notes and other documents, but failed to formally offer all related documents.
On August 3, 2017, RTC dismissed the complaint citing insufficient evidence on the deficiency claim.
Upon SPV-AMC, Inc.'s motion for reconsideration, the RTC admitted additional evidence attached to the motion and rendered judgment in favor of SPV-AMC, Inc. ordering petitioners to pay P13,268,303.02 plus interests and costs.

Petitioners filed a petition for certiorari to the Court of Appeals (CA), which dismissed the petition on procedural grounds for failure to file a motion for reconsideration and because appeal, not certiorari, was the proper remedy.
The CA denied a subsequent motion for reconsideration.
Petitioners filed the present Petition for Review on Certiorari to the Supreme Court.

Whether the CA erred in dismissing the petition for certiorari outright on procedural grounds.
Whether petitioners were required to file a motion for reconsideration before filing the petition for certiorari.

Whether the RTC gravely abused its discretion in considering documents that were not formally offered in evidence, in violation of Section 34, Rule 132 of the Rules of Court.
Whether the RTC erred in awarding the deficiency claim of P13,268,303.02 despite insufficient evidence supporting the claim.