One of the major discussion points was whether the scheme should be opt in, ie a civil partnership type scheme for heterosexual cohabitants, or opt out, ie it should apply to all eligible cohabitants unless they specifically agree otherwise. (newlawjournal.co.uk)
However, Fano pointed to a few partnership types it will target. (inc.com)
If the scheme is intended to give safety net protection to vulnerable cohabitants then it would fail if it required couples to have first gone through a marriage / civil partnership type ceremony or registration. (newlawjournal.co.uk)