Where two people register as civil partners of each other in Northern Ireland, the civil partnership is void if—
at the time when they do so, they are not eligible to register as civil partners of each other under Chapter 1 (see section 138), or
at the time when they do so they both know—
that due notice of proposed civil partnership has not been given,
that the civil partnership schedule has not been duly issued,
that the place of registration is a place other than that specified in the civil partnership schedule, or
that a registrar is not present.
Subsection (3) applies in the case of a civil partnership which results from the conversion, or purported conversion, of a marriage into a civil partnership under Part 3, 4 or 5 of the Marriage and Civil Partnership (Northern Ireland) (No. 2) Regulations 2020.
The civil partnership is void if (but only if) the marriage was void.