Should have done it like Shikoku Bank for the staff to commit seppuku if found engaged in embezzling and frauds:

This pledge is a part of the 37th National Bank, the predecessor of Shikoku Bank, in order to comply with the strict handling of bills, all 23 employees including the president of Miura signed and stamped the blood seal.

In the event of fraud in the transaction, he vowed to pay for it with private money and seppuku. It conveys the weight of ethics and responsibility not only as a banker but also as a member of society, and is said to be the greatest treasure of Shikoku Bank.

https://www.shikokubank.co.jp/profile/seiyaku.html
https://en.wikipedia.org/wiki/Shikoku_Bank