(a) Prior to 15 Days of Trial Date. A party may file an amendment to a pleading at any time prior to 15 days of a scheduled trial date. Within 15 days after service of an amendment, any other party to the action may file a motion to strike setting forth reasons why the court should not allow the amendment. A notice of intention to defend previously filed pursuant to Rule 3-307 shall apply to the amendment. An adverse party who has not previously filed a notice of intent to defend shall do so within ten days after service of the amended pleading.

(b) Within 15 Days of Trial Date and Thereafter. Within 15 days of a scheduled trial date or after trial has commenced, a party may file an amendment to a pleading only by written consent of the adverse party or by leave of court. If the amendment introduces new facts or varies the case in a material respect, the new facts or allegations shall be treated as having been denied by the adverse party. The court shall not grant a continuance or mistrial unless the ends of justice so require.

(c) Scope. An amendment may seek to (1) change the nature of the action, (2) set forth a better statement of facts concerning any matter already raised in a pleading, (3) set forth transactions or events that have occurred since the filing of the pleading sought to be amended, (4) correct misnomer of a party, (5) correct misjoinder or nonjoinder of a party so long as one of the original plaintiffs and one of the original defendants remain as parties to the action, (6) add a party or parties, (7) make any other appropriate change. Amendments shall be freely allowed when justice so permits. Errors or defects in a pleading not corrected by an amendment shall be disregarded unless they affect the substantial rights of the parties.

(d) If New Party Added. If a new party is added by amendment, the amending party shall cause a summons and complaint, together with a copy of all pleadings, scheduling notices, court orders, and other papers previously filed in the action, to be served upon the new party.

Source: This Rule is derived as follows:

Section (a) is derived from former Rule 320.

Section (b) is new and is derived in part from former Rule 320 e.

Section (c) is derived from sections a 2, 3, 4, b 1 and d 5 of former Rule 320 and former Rule 379.

Section (d) is new.