Below is a comprehensive discussion on Rule 39 of the Philippine Rules of Court, specifically focusing on when execution shall issue under Section 1 (and related provisions) on Execution, Satisfaction, and Effect of Judgments. This summary integrates the relevant rules, jurisprudential principles, and procedural nuances.

I. GENERAL RULE ON WHEN EXECUTION SHALL ISSUE

1. Execution as a Matter of Right (Rule 39, Section 1(a))

Period to Appeal Has Lapsed Without an Appeal
- A judgment or final order becomes final and executory once the period to appeal (generally 15 days from receipt of the judgment or final order, unless a different period is provided by law or rules) expires without a party having filed a notice of appeal or appropriate post-judgment motion (e.g., motion for reconsideration or new trial).
- Upon finality, execution becomes a matter of right for the prevailing party. This means that the court must issue the writ of execution if all conditions for finality are met.
No Perfection of Appeal
- If a party attempts to appeal but fails to comply with the rules (e.g., failure to pay appellate docket fees, failure to file within the reglementary period), the appeal is not perfected, and the judgment attains finality. The successful party may then move for execution as a matter of right.

2. Effect of a Perfected Appeal on Execution

When a valid, timely appeal has been made, the lower court generally loses jurisdiction over the case (subject to certain exceptions, like resolving issues collateral to the appeal or dealing with enforcement of a judgment for a co-party not appealing). In such a scenario, no execution can issue from the trial court unless there is execution pending appeal granted under special circumstances (see below).

II. DISCRETIONARY EXECUTION (EXECUTION PENDING APPEAL)

1. Grounds and Procedure (Rule 39, Section 2)

Motion for Execution Pending Appeal
- Even if an appeal is timely filed, the prevailing party may file a motion for execution pending appeal in the trial court. This is also referred to as an “execution pending appeal” or a “discretionary execution.”
- Requirements:
  1. Good Reasons: The movant must establish compelling or “good reasons” in a written motion.
  2. Hearing and Due Notice: The motion must be set for hearing with due notice to all parties.
- The court must state in a special order the good reasons justifying the issuance of the writ of execution despite the pending appeal.

2. Jurisprudential Guidance on “Good Reasons”

The Supreme Court of the Philippines has consistently held that “good reasons” must be exceptional circumstances that justify immediate enforcement of the judgment (e.g., irreparable injury, urgent public interest, preservation of property from imminent danger or loss).
A bare invocation that the prevailing party “urgently needs” relief is generally insufficient. Concrete, specific facts must show that waiting for the appeal to run its course would result in grave injustice or irreparable prejudice.

3. Effect of Improperly Granted Discretionary Execution

If execution pending appeal is granted without valid grounds or without a hearing, such issuance may be nullified or stayed by the appellate court upon the aggrieved party’s motion or petition.

III. SPECIAL INSTANCES AFFECTING WHEN EXECUTION SHALL ISSUE

1. Judgment by Default

Once a judgment by default becomes final (if the defendant fails to appeal or move for reconsideration/new trial), execution shall issue as a matter of right upon motion.
If defendant appeals, the same rules on discretionary execution may apply if the plaintiff seeks immediate enforcement.

2. Judgments in Summary Procedure and Small Claims

In cases governed by Summary Procedure (e.g., certain civil cases with a low amount in controversy, unlawful detainer, forcible entry) or in Small Claims actions, the period to appeal and the timeline for finality may be shorter. Once final, execution likewise follows as a matter of right.

3. Partial Judgment or Separate Judgment

If the court renders a partial judgment under Rule 36, Section 5 (or a separate judgment on some issues), that partial/separate judgment can become final and executory if no appeal is taken on it. Execution of that partial or separate judgment may issue while the remaining claims proceed, provided the court so directs.

IV. PROCEDURE FOR SECURING THE WRIT OF EXECUTION

1. Motion for Execution

Even when execution is a matter of right (i.e., judgment final and executory), it is still generally required to file a motion for issuance of the writ of execution.
Courts do not typically issue the writ motu proprio (on their own) except in special cases (e.g., judgments for support pendente lite).
The motion should succinctly state the finality of the judgment/order and ask for issuance of the writ.

2. Issuance of the Writ

The clerk of court prepares the writ upon the order of the court.
The writ of execution directs the sheriff or other proper officer to enforce the judgment against the property or person of the losing party, in accordance with the nature of the judgment (e.g., sum of money, delivery of property, specific performance, etc.).

3. Notice to Adverse Party

Basic due process requires that the adverse party be notified that a motion for execution has been filed. Normally, if the judgment is already final and executory, the scope of the opposition is very limited—often relating only to whether the judgment has truly become final.

V. STAY OR QUASHAL OF EXECUTION

1. Stay of Execution Pending Appeal

If the trial court granted discretionary execution without sufficient grounds, the aggrieved party can seek a restraining order or injunctive relief before the Court of Appeals (or the Supreme Court, depending on the hierarchy of courts).
The appellate court examines if the lower court abused its discretion in granting execution pending appeal.

2. Quashal/Recall of Writ Improvidently Issued

Even after a writ of execution has been issued, a motion to quash or recall the writ may be filed if there is a showing that:
1. The writ of execution varies the terms of the judgment;
2. The judgment has been satisfied or supervening events make it unjust or impossible to enforce;
3. There is a lack of due notice or a significant procedural defect.

VI. KEY JURISPRUDENTIAL POINTS

Distinction Between Finality of Judgment and Writ of Execution
- A judgment’s finality gives a vested right to execution, but the prevailing party must still generally file a motion to secure the writ.
Supervening Events
- Even if a judgment is final and executory, a supervening event (a new fact or circumstance transpiring after finality) may render execution unjust or impossible. In such cases, courts may stay or modify execution.
Good Reasons in Discretionary Execution
- The Supreme Court has repeatedly stressed that discretionary execution is not a matter of right; it must be founded on solid, compelling reasons (e.g., immediate enforcement is urgent to prevent irreparable harm, or public policy considerations).
Public Policy to Expedite Litigation
- Courts carefully evaluate motions for execution to avoid undue delay. Once final, execution is the final stage of litigation—a mechanism ensuring the prevailing party enjoys the fruits of a favorable judgment.

VII. PRACTICAL POINTERS

Monitor the Appeal Period
- Counsel for the prevailing party should closely monitor the expiration of the appeal period to promptly file a motion for execution when no appeal is perfected.
Document the Finality of Judgment
- Always secure certified true copies of relevant orders or entries of judgment from the clerk of court to show that the decision has become final and executory.
Verify All Parties Concerned
- Make sure to join all parties bound by the judgment when moving for execution (and specify any partial settlement or compromise).
Prepare to Oppose Discretionary Execution
- If you represent the losing party on appeal, be ready to contest any motion for discretionary execution by demonstrating the absence of “good reasons.”
Seek Prompt Relief from Appellate Courts
- In cases of an improvidently issued writ, counsel must act swiftly to file the appropriate remedy (certiorari, prohibition, or injunctive relief) with the Court of Appeals or Supreme Court, as the case may be.

VIII. CONCLUSION

Under Rule 39 of the Philippine Rules of Court, the overarching principle is that execution shall issue as a matter of right once a judgment becomes final and executory (i.e., the period to appeal has lapsed without perfection of an appeal). However, execution can also be obtained pending appeal through discretionary execution, contingent on specific, compelling grounds and subject to the trial court’s sound exercise of discretion. Once issued, a writ of execution may still be stayed or quashed if supervening events justify it or if the writ improperly varies the terms of the judgment. Proper observance of procedural requirements and careful presentation of evidence on the timeliness and grounds for execution are crucial to ensuring correct and efficient enforcement of judgments.

Note: This discussion is based on the Rules of Court (as amended) and relevant Philippine jurisprudence. For specific legal strategies or a detailed application of these principles to a particular case, it is imperative to consult full-text rules, updated Supreme Court decisions, and/or seek professional legal counsel.