Seyler & Tillemann was a Hamburg bank in the mid 18th century, that went bankrupt in 1763. It was owned by the merchants Abel Seyler and Johann Martin Tillemann, and notably involved itself in the currency market and speculation with financial instruments. It also owned a large silver refinery in Hamburg. Abel Seyler later became famous as a theatre director, and was the father of the noted banker L.E. Seyler, the senior partner of Berenberg Bank for nearly half a century.