  The Hard Lefschetz Property (HLP) has recently been formulated in the context
of isometric flows without singularities on manifolds. In this category, two
versions of the HLP (transverse and not) have been proven to be equivalent,
thus generalizing what happens in the important cases of both K-contact and
Sasakian manifolds. In this work we define both versions of the HLP for
almost-free S3 -actions, and prove that they agree for actions satisfying a
cohomological condition, which includes the important category of 3-Sasakian
manifolds, where those two versions of the HLP are shown to be held. We also
provide a family of examples of free actions of the 3-sphere which are not
3-Sasakian manifolds, but satisfy the HLP.
