I note David Sellar - an ex Lord Lyon - has written about clans that
'By way of definition, it has been suggested that, ‘Clann was used to describe a patrilineal kindred the members of which descended in known steps from a named ancestor’(From David Sellar’s, ‘Clans, origin of’ in Derrick S Thomson (ed.) Companion to Gaelic Scotland Oxford 1983) This definition underlines two points believed to be true of the clan in Scotland and in Ireland: namely that the members of the true clan were related to one another through the male line, and that the eponym or name father of the clan was a historical, and not a mythical, character. '
(Page 92 David Sellar, Chapter 4 The Family, in ed. E. J. Cowan and L. Henderson A History of of Everyday Life in Medieval Scotland, 1000 to 1600, Edinburgh University Press, Edinburgh, 2011.)
In other words clans require a central, historically real, male founder to be an historic / traditional clan. Given Gunns do not have such descent - note earlier entries showing that Gunn descent from a supposed Orkney Islands founder is ridiculous (Gunn is a 'regional name' for very early - and non kindred - inhabitants of Strathnaver / Sutherland / Caithness) then on historic / academic definitions Gunns are not a clan...
'Chief Ottar Snaekollsson Gunn' did not exist; another reason why Gunns have no Orkney origin
Some believe that there was a 'Chief Ottar Snaekollsson Gunn' (see Mark Rugg Gunn's book pages 31- 32) who was the supposed son of 'Chief Snaekoll Gunn'. This Ottar is by inference the proof that somehow Snaekoll made it back to Scotland and so the Gunn Orkney origin idea is true. The Gunn Orkney islands / Viking / Norse origin myth fails all the tests including this Ottar Snaekollson test.
It fails because we know about when Snaekoll was born (roughly 1200) as his mother's first husband (not the 'Gunn') is well known and he died in the Battle of Wick in 1198. The academic reference to an 'Ottar Snaekollson' meeting King Hakon in Bergen is certainly correct. But the meeting is in 1224. That's right, 1224, so any son of Snaekoll would be lucky to be four years old and would certainly not be sent to negotiate with a King! And Snaekoll's marriage / children would have been mentioned in the 'Orkneyinga Saga' as his life is very much detailed in that text and it is not mentioned.
The Hebrideans who went to Bergen to negotiate with the King in 1224 did take an Ottar Snaekollson but he was an important Sudreyan Chief living on the west coast of Scotland and the right sort of man to negotiate with a King.
So there goes 'Ottar Snaekollson supposed Chief Gunn'; he has no role in any Gunn history. And it's another nail in the ridiculous Gunn Orkney founder origin idea...