Does SP3 not sign authn requests by default?

[Wessel, Keith]

We have a multi-domain SP hosting a number of CPanel sites. It automatically pulled in SP 3.0 (they clearly need to fix how the prod environment gets updated), and now they're having authentication problems. It's one of the few SPs for which we've allowed the skip endpoint validation if signed option in the IdP.

Before, the authn requests were signed, and everything was working with the endpoint validation checks being skipped. Is this no longer the default in SP V3? And if not, how do we turn it back on?

Thanks,
Keith