In this Part of this Act a "rent agreement with a tenant having security of tenure" means—
an agreement increasing the rent payable under a protected tenancy which is a regulated tenancy, or
the grant to the tenant under a regulated tenancy, or to any person who might succeed him as a statutory tenant, of another regulated tenancy of the dwelling-house at a rent exceeding the rent under the previous tenancy.
Where any rates in respect of the dwelling-house are borne by the landlord or a superior landlord, any increase or rent shall be disregarded for the purposes of the definition in subsection (1) above if the increase is no more than one corresponding to an increase in the rates borne by the landlord or a superior landlord in respect of the dwelling-house.
If—
a rent agreement with a tenant having security of tenure takes effect on or after the commencement of this Act, and was made at a time when no rent was registered for the dwelling-house under Part IV of this Act, . . .
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the requirements of subsection (4) below shall be observed as respects the agreement.
The requirements are that—
the agreement is in writing signed by the landlord and the tenant, and
the document containing the agreement contains a statement, in characters not less conspicuous than those used in any other part of the agreement—
that the tenant's security of tenure under this Act will not be affected if he refuses to enter into the agreement, and
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that entry into the agreement will not deprive the tenant or landlord of the right to apply at any time to the rent officer for the registration of a fair rent under Part IV of this Act,
or words to that effect, and
the statement mentioned in paragraph (b) above is set out at the head of the document containing the agreement.