(1) In section 4(1) of the Principal Act insert the following definitions—
"" domestic partner" of a person means—
(a) a person who is in a registered domestic relationship with the person; or
(b) a person with whom the person is in a domestic relationship;
"domestic relationship" means a relationship between 2 persons who are living together as a couple on a genuine domestic basis (irrespective of sex or gender) and who are neither married to each other nor in a registered domestic relationship with each other;
"registered domestic relationship" has the same meaning as in section 3 of the Relationships Act 2008 ;".
(2) In section 4(1) of the Principal Act—
(a) the definition of de facto relationship is repealed ;
(b) the definition of de facto spouse is repealed .
(3) For section 4(5) of the Principal Act substitute —
"(5) If a person living in a domestic relationship is also in a registered domestic relationship, a reference in this Act (except in section 55) to a domestic partner of such a person does not include a reference to the person with whom the first-mentioned person is in the registered domestic relationship.".
(4) In section 4(6) of the Principal Act, for "man or woman" substitute "person".
(5) After section 4(6) of the Principal Act insert —
"(7) For the purposes of the definition of domestic partner in subsection (1), in determining whether persons who are not in a registered domestic relationship are domestic partners of each other, all the circumstances of the relationship are to be taken into account, including any one or more of the matters referred to in section 35(2) of the Relationships Act 2008 as may be relevant in a particular case.
(8) For the purposes of subsection (7), a person is not a domestic partner of another person only because they are co-tenants.".