420. Rent from tenancies binding on mortgagee.

As regards tenancies created before the mortgage or created by the mortgagor after the mortgage under an express or statutory power1, the mortgagee, as he is entitled to the reversion, may require payment to himself of all arrears of rent existing when he goes into possession2. He is entitled to arrears of rent, whether falling due before or after the mortgage was granted, and the claim of the mortgagee will prevail over the claim of persons to whom the rents have been assigned by the mortgagor3. The mortgagee can recover also an increased rent which the tenant has agreed