Friedberg 205 (W-3970). 1863 $500 Interest Bearing Note. PCGS Currency Very Choice New 64. Face and Back Proof.Offered is an incredible face and back proof pair representing this otherwise unknown 1863 $500 Interest Bearing Note type. Both face and back proofs are on India paper mounted to the same card. The face displays a bald eagle with nest at center, Liberty with anchor and flag at left and three interest coupons at right. Engraved signatures of Chittenden and Spinner are found in the signature panels while a large green protector panel flanked by Roman numeral Ds is centered near bottom. These $500 Interest Bearing Notes were produced by the American Bank Note Company and bore 5% interest per annum. The back proof is ornately printed in bold green inks and features an intricate decorative device at left (reverse of the coupons) with a large Roman numeral D centered. The primary back design displays the clause and anti-counterfeiting language at center with large 500 counters on either side. Two punch cancellations are observed in each signature panel. Only $50 and $100 notes from this series are known in issued form and both are prohibitively rare. No issued $500 and $1000 notes are known to exist. We have only seen the present face proof; we know of one other example of the back proof. This is an incredible pair and a necessity for any serious collector of these "Middle of the Book" Interest Bearing Notes.