Jupiter Mortgage No.1 PLC is a static RMBS transaction that securitizes a portfolio of £3.005 billion owner-occupied and buy-to-let (BTL) mortgage loans secured on properties in the U.K. At closing, the seller (Jupiter Seller Ltd.) purchased the beneficial interest in the portfolio from the sponsor (Citibank N.A., London Branch), who in turn acquired the portfolio from the original sellers, NRAM Ltd. and Bradford and Bingley PLC (B&B). The issuer used the issuance proceeds to purchase the full beneficial interest in the mortgage loans from the seller. The issuer granted security over all of its assets in favor of the security trustee. The pool is well seasoned. Most of the loans are first-lien U.K. owner-occupied and BTL residential mortgage loans, however