10 Pounds Allied Irish Banks

Allied Irish Banks issued its own sterling-denominated notes for circulation in Northern Ireland, a practice permitted under the Currency and Bank Notes Act 1928 and its successors, which allowed certain commercial banks to maintain note-issuing rights in the province. AIB's entitlement derived from its 1966 acquisition of the Munster & Leinster Bank, one of the original authorized issuers, though by the late 1980s the practical volumes in circulation were modest against the dominant Bank of England and Bank of Ireland issues.

De La Rue's involvement was continuous across the series, with the watermark serving as the primary security element — relatively spare by the standards of contemporaneous European issues.