Subject to subsection (3), a person may lodge a caution against the registration of title to an unregistered legal estate if he claims to be—
the owner of a qualifying estate, or
entitled to an interest affecting a qualifying estate.
For the purposes of subsection (1), a qualifying estate is a legal estate which—
relates to land to which the caution relates, and
is an interest of any of the following kinds—
an estate in land,
a rentcharge,
a franchise, and
a profit a prendre in gross.
No caution may be lodged under subsection (1)—
in the case of paragraph (a), by virtue of ownership of—
a freehold estate in land, or
a leasehold estate in land granted for a term of which more than seven years are unexpired;
in the case of paragraph (b), by virtue of entitlement to such a leasehold estate as is mentioned in paragraph (a)(ii) of this subsection.
The right under subsection (1) is exercisable by application to the registrar.