Could users outside Bell Labs actually get their hands on post-v7 Research Unixes?

It was always my impression that The Thing You Could Get From The Phone Company, after v7, was System III or System V.  Obviously it's not surprising that Research Unix features from later versions ended up in SysV, but did anyone actually learn about them from v8-v10, or just by way of SysV ?

Was there some (legal) mechanism for the post-v7 Unixes to get out into people's hands?

Adam