3. Under what circumstances should defendant be permitted to assert a compulsory counterclaim after the applicable statute of limitations has run? Formerly Federal Rule 13

(f) allowed a pleader to obtain leave of the court to assert a counterclaim that was omitted

“through oversight, inadvertence, or excusable neglect or if justice so requires.” In 2009 subsection

(f) was abrogated, with the aim of making clear that the decision to allow an omitted counterclaim after the statute of limitations has lapsed is governed exclusively by Federal Rule 15 and, like other pleading amendments, may benefit from relation back.