Method, apparatus and system embodiments provide a register to track the oldest exception event or sticky event in a processor. The processor may be an out-of-order processor. Dispatched instructions (or micro-ops) may be maintained in a queue, such as a reorder buffer (ROB), for in-order retirement. For at least one embodiment, event information is maintained only in the register and is not maintained in a ROB. For at least one other embodiment, event information is maintained in a ROB entry for some events and in the register for others. For such latter embodiment, a retire engine takes the contents of both the ROB entry and the register into account when determining whether to take an exception or otherwise initiate a handling sequence during in-order instruction retirement. Other embodiments are also described and claimed.