Inherent bonus

A bonus to an ability score resulting from powerful magic, such as a wish. Inherent bonuses cannot be dispelled. A character is limited to a total inherent bonus of +4 to any ability score. Multiple inherent bonuses to a particular ability score do not stack, so only the best one applies. Most inherent bonuses to ability scores result from reading tomes. Inherent bonuses to ability score are kept with any form of reincarnation. They apply gradually as you level up (+1 at 3rd level, +2 at 7th, +3 at 11th, and +4 at 15th).

Several items grant inherent bonus to various game characteristics. These bonuses stack with the most common bonuses.
 * Reinforced Plating items
 * inherent resistance items, e.g. Trial by Fire (item)