(1) Whenever the claim or defense asserted in the amended pleading arose out of the conduct, transaction, or occurrence set forth or attempted to be set forth in the original pleading, the amendment relates back to the date of the original pleading.
Rule 15.03.Relation back of amendments.
Current through June 18, 2026 · Last verified July 9, 2026
In one sentenceThis rule lets an amended pleading date back to the original filing when the new claim or defense grew out of the same conduct, transaction, or occurrence, and sets conditions for substituting a new defendant without losing that earlier filing date.
Full Text of Rule 15.03
(2) An amendment changing the party against whom a claim is asserted relates back if the condition of paragraph (1) is satisfied and, within the period provided by law for commencing the action against him, the party to be brought in by amendment (a) has received such notice of the institution of the action that he will not be prejudiced in maintaining his defense on the merits, and (b) knew or should have known that, but for a mistake concerning the identity of the proper party, the action would have been brought against him.
(3) The delivery or mailing of process to the attorney general of the Commonwealth, or an agency or officer who would have been a proper defendant if named, satisfies the requirement of paragraph (2) with respect to the Commonwealth or any agency or officer thereof to be brought into the action as a defendant.
Amendment History
(Amended October 18, 1977, effective January 1, 1978.)
Plain-English Summary
When a party amends a complaint or answer, the amendment normally counts as filed on the day it's submitted. Rule 15.03 changes that in one situation: if the new claim or defense arises from the same conduct, transaction, or occurrence already described in the original pleading, the amendment relates back to the date the original pleading was filed. That matters most when a statute of limitations has run in the meantime, because the earlier filing date can save the claim.
The rule also covers amendments that swap in a new defendant. Changing who's being sued relates back only if the underlying claim meets the same-transaction test above, and the new party learned of the lawsuit in time to defend without prejudice, and knew or should have known the suit would have named him but for a mistake about identity. The rule adds a specific path for cases against the Commonwealth: delivering or mailing process to the attorney general, or to the agency or officer who should have been named, satisfies the notice requirement for bringing in the Commonwealth or one of its agencies as a defendant.
Frequently Asked Questions
If I amend my complaint after the statute of limitations runs, does the new claim still count as timely?
It can. Under Rule 15.03, an amendment relates back to the date of the original pleading if the claim or defense in the amendment arose out of the same conduct, transaction, or occurrence already set out in the original pleading.
Can I add or substitute a defendant after the deadline to sue has passed?
Yes, if the conditions in Rule 15.03(2) are met: the claim arises from the same transaction or occurrence, and within the period allowed for suing that party, the new party received enough notice of the suit that defending on the merits won't be prejudiced, and knew or should have known the action would have named him but for a mistake about identity.
How do I satisfy the notice requirement when adding the Commonwealth of Kentucky as a defendant?
Rule 15.03(3) says delivering or mailing process to the attorney general, or to an agency or officer who would have been a proper defendant if named, satisfies the notice condition for bringing the Commonwealth or one of its agencies or officers into the action.
Source & verification. The rule text is reproduced verbatim from the
official Kentucky Rules of Civil Procedure (Ky. R. Civ. P. 15.03). Prescribed by the Supreme Court of Kentucky (Ky. Const. § 116). The plain-English summary is original and written by us. Last verified July 9, 2026. ·
Official source
Also known as: relation back amendmentamending complaint after statute of limitationsadding a new defendant latechanging defendant name in lawsuitnotice to attorney general Kentucky lawsuitdoes an amended pleading count as the original filing date