Bonds thay can be redeemed by the investor, instead of the issuer on a set date and price are known as Put or Putable Bonds.
These are normally issued by companies who have financial difficulty attracting bond investors. These bonds are fairly rare as they can be devestating to a companies balance sheet. This feature is very attractive to bond investors. Should interest rates rise, bond holders can "Put" the bond back to the issuer and find other attractive yields elsewhere.
This places the issuer in a difficult financial capacity, as they will most likely have to borrow at even higher rates if many investors put the bonds back to them in a short period of time.
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