A 2008 analysis of the Austronesian Basic Vocabulary Database fully supported the unity of the Celebic languages. It determined the internal structure to be as follows:
- Southeast Celebic (85% confidence)
The Tomini–Tolitoli languages were not covered by the study, but previous classifications had placed them in with the Southeast Celebic family.
External relationships 
Sulawesi has a diverse set of languages. The families of the north—Gorontalo, Sangiric, and Minahasan languages—have the Austronesian alignment system of syntax common to the languages of the Philippines and Borneo, and reconstructed for proto-Malayo-Polynesian.
The languages of the center and south of the island have lost this system. Wouk and Ross (2002) argued from this that Sulawesi was the center of dispersal for a group of languages which share this loss, which they call Nuclear Malayo-Polynesian. They leave Gorontalo, Sangiric, and Minahasan outside their Nuclear MP, and the various other Sulawesi families as primary branches of Nuclear MP. Adelaar and Himmelmann (2005) go further and classify Gorontalo, Sangiric, and Minahasan as Philippine languages, with Gorontalo in a "Greater Central Philippine" branch along with Tagalog.
However, the 2008 study only supported the inclusion of Gorontalo with the Philippine languages, as a coordinate branch (100% support for Gorontalo–Philippines and a primary division into Gorontalo vs Philippine languages). Moderate (80%) support was found for unifying Sangiric and Minahasan; like the other groups of Sulawesi, South Sulawesi and Celebic, lexically at least these appear to lie within Nuclear Malayo-Polynesian and are perhaps most closely tied within that group to Central–Eastern Malayo-Polynesian. Celebic may be closer to Central–Eastern than to Sangir–Minahasan or South Sulawesi. (See Nuclear Malayo-Polynesian.)
Further reading 
- Mead, David. 2003. "Evidence for a Celebic supergroup." In Issues in Austronesian historical phonology, John Lynch (ed.). pages 115-141. Pacific Linguistics 550. Canberra: Pacific Linguistics, Research School of Pacific and Asian Studies, Australian National University.
- Mead, David. 2003. "The Saluan-Banggai micro group of eastern Sulawesi." In Issues in Austronesian historical phonology, John Lynch (ed.). pages 65-86. Pacific Linguistics 550. Canberra: Pacific Linguistics, Research School of Pacific and Asian Studies, Australian National University.
- Fay Wouk and Malcolm Ross (ed.), The history and typology of western Austronesian voice systems. Australian National University, 2002.
- K. Alexander Adelaar and Nikolaus Himmelmann, The Austronesian languages of Asia and Madagascar. Routledge, 2005.
- Austronesian Basic Vocabulary Database, 2008.