What is stamping (of a security)?

Writing down a security means lowering the nominal value of a security, such as a share or a bond, usually because the issuing institution is in financial difficulty. With shares, this happens in proportion to the amount by which one wishes to reduce the share capital.

For bonds, the principal sum is, for example, lowered to a percentage, such as 70%. This concept became particularly relevant during the debt crisis of 2011, where countries such as Greece and Portugal tried to reduce their national debt through write-downs. This process is also referred to as restructuring or reprofiling.