To a quiver Q and choices of nonzero scalars $$q_i$$
q
i
, non-negative integers $$\alpha _i$$
α
i
, and integers $$\theta _i$$
θ
i
labeling each vertex i, Crawley-Boevey–Shaw associate a multiplicative quiver variety$${\mathcal {M}}_\theta ^q(\alpha )$$
M
θ
q
(
α
)
, a trigonometric analogue of the Nakajima quiver variety associated to Q, $$\alpha $$
α
, and $$\theta $$
θ
. We prove that the pure cohomology, in the Hodge-theoretic sense, of the stable locus $${\mathcal {M}}_\theta ^q(\alpha )^{{\text {s}}}$$
M
θ
q
(
α
)
s
is generated as a $${\mathbb {Q}}$$
Q
-algebra by the tautological characteristic classes. In particular, the pure cohomology of genus g twisted character varieties of $$GL_n$$
G
L
n
is generated by tautological classes.