Dwarf galaxies are assumed to follow the same principle outside host galaxies between dual tandem Galaxy Anchor Black Holes.
However to create equal massive BHs, I assume that the same process could be in action as observed in the Eagle (Spire) nebula. see below.
The LIGO observatory should be able to observe small BH splitting in nearby nebula as observed in the Eagle nebula.
see also:
The Self Organizing Universe in three different Nebula systems.
http://vixra.org/pdf/1304.0022v6.pdf
and:
https://bigbang-entanglement.blogspot.nl/2017/11/weve-found-bunch-of-dwarf-galaxies-we.html
Model for the merging and splitting black hole systems.