Shape operators with positive eigenvalues

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I am working on the frame of singular Riemannian foliations and I am interested on examples of foliations whose eigenvalues of the shape operator of a given leaf are all positive. One intermediate step to understand such examples consists in to understand the following:

Given a Riemannian manifold $(M,g)$ and an immersed manifold $N$. Let $A$ be the shape operator on $N$. In which conditions on $M$ and $N$, $A$ has positive eigenvalues for any point?

It follows, in particular, that if the shape operator is positive definite, then the claim follows.