The Pirates have left the door open for the option being exercised. This allows the club to retain some leverage in case of a possible trade.
"We have not officially determined that we are going to decline the option," Pirates GM Neal Huntington said.
Huntington's comments came after team president Frank Coonelly told a Pittsburgh-area radio station that the team was unlikely to exercise the option and that the Pirates had already informed Maholm of that decision.
There is a $750,000 buyout if the one-year option is not picked up.
Maholm, a first-round draft pick in 2003, went 6-14 this season -- though he often had poor run support -- and finished the season on the disabled list because of a strained shoulder.