The Ancient Greek perfect tense poses an interesting empirical puzzle involving reduplication. While consonant-initial roots display a phonologically regular alternation based on cluster type, vowel-initial roots display two distinct patterns whose distribution is not phonologically predictable. The reduplicative grammar that generates the consonantinitial patterns is directly compatible with the productive vowel-initial pattern, vowel lengthening. The minority vowel-initial pattern, “Attic reduplication,” both its shape and its distribution, can be explained as a phonotactic repair that operated at a prior stage of the language. This pattern was later reanalyzed, such that Attic reduplication is retained not as a phonotactic repair but through lexical indexation.