421. Rent from tenancies not binding on mortgagee.

Where after the mortgage a tenancy is created which is not binding on the mortgagee1, he is not entitled to demand payment of the rents as such, but after notice from him to the tenants to pay the rents to him they must not pay rents to the mortgagor, and they are justified in paying the rents to the mortgagee, as otherwise, on recovering possession, he would be entitled to recover the rents as mesne profits2. Technically, the claim for mesne profits is for trespass and requires that the mortgagee is to have been in possession during the time