I only looked up a handful, but the ones I looked up...
United Center and American Airlines Center (Dallas) are 50/50 jointly held between the basketball and hockey franchises.
Rose Garden, Scotiabank Centre and Madison Square Garden are held by their basketball tenants' corporate parent.
Barclay's Center, Toyota Center, Spectrum Center (Charlotte), AT&T Center (San Antonio), and American Airlines Arena (Miami) are owned by the local municipality.
TD Garden and Staples Center are owned by different corporations.