A Deed Poll is an incredibly rare but legal process of changing one's family name. It is a power, like Legitimization, that is reserved only for monarchs and Lords.
This act is similar to legitimization, but unlike the latter, only legitimate nobles can apply to this. Bastards do not apply (although a bastard could apply if they have been legitimized). A noble can only change his or her name if they are descended from a particular house, and can only change it to the name of that house.
Given the laws and customs of Westeros, the act would only make sense with men, as women would still typically change their family name to that of their husbands. Also, the act would only seem necessary if a noble house would otherwise become extinct, or has been extinct for years, such as House Reyne.
- Ser Claron Deddings, asked to become a Reyne in 279 AL (being descended from House Reyne), but was refused by King Aerys II, given the crimes that House Reyne had committed before being wiped out.
- Ser Harrold Hardyng is set to become lord of the Eyrie should Robert Arryn die without an heir. Being second cousin to Lord Robert, he would ascend as "Harrold Arryn" should Robert die under these circumstances.