Semi legal means, it is generally not ollegal to form a club or association of any kind be it by Citizens, or Union Residents and no registtration laws exist (on Union Level).
However technically the Union Citizen right for free an unregulated assembly is not extended to Non Cits (Since Assembly Resolution 01-01 3412 )
But as long as the Club or association is not promoting crimes or unlawful behavior , no actions are taken.
Many drift clubs are too small to be of real concern to the Union Police , and some are even registered asociations (Associations, Clubs and religions can register (not required)
However some Drift Clubs are known to engage in criminal activities such as the Bad News .