A property whose values (other than a default value), once associated with a specific code point, are fixed and will not be changed, except to correct obvious or clerical errors.

• For a fixed property, any default values can be replaced without restriction by actual property values as new characters are assigned to previously unassigned code points. Examples of fixed properties include Age and Hangul_Syllable_Type.
• Designating a property as fixed does not imply stability or immutability. While the age of a character, for example, is established by the version of the Unicode Standard to which it was added, errors in the published listing of the property value could be corrected. For some other properties, even the correction of such errors is prohibited by explicit guarantees of property stability.