The following animated objects share the same EditorID:
AnimObjectDrawBlade [ANIO:02013794] (Dawnguard.esm)
AnimObjectDrawBlade [ANIO:0300A256] (HearthFires.esm)
AnimObjectWoodScrap [ANIO:02013795] (Dawnguard.esm)
AnimObjectWoodScrap [ANIO:03014352] (Hearthfires.esm)
The following idle animations share the same EditorID:
IdleChildCryingStart [IDLE:020029D3] (Dawnguard.esm)
IdleChildCryingStart [IDLE:030182FF] (Hearthfires.esm)
IdleChildCryingEnd [IDLE:020029D4] (Dawnguard.esm)
IdleChildCryingEnd [IDLE:03018300] (Hearthfires.esm)
I am not sure whether the EditorIDs matter in case of animated objects and idle animation, or whether they are referenced somewhere. But the CK adds "DUPLICATE01" to the Hearthfires one if you load both in an active file and resave.