  We determine the supersymmetric AdS_7 backgrounds of seven-dimensional
half-maximal gauged supergravities and show that they do not admit any
deformations that preserve all 16 supercharges. We compare this result to the
conformal manifold of the holographically dual (1,0) superconformal field
theories and show that accordingly its representation theory implies that no
supersymmetric marginal operators exist.
