Oil Seepage

Many times people think it’s the oil pump, but actually it’s coming from the bottom of the gearbox. Clean the area good then keep a watch on it. If it’s the gearbox then you’ll have oil up to it’s base. If it’s the oil pump the oil will be lower. If it is the pump then replace the “O” ring. It’s easy to do. 

Trapped oil in the oil pump cavity is most common. 

Sometimes when you remove the oil pump (to change o-rings), oil gets caught in the oil pump cavity and it will seep out over time until all the trapped oil in the cavity is gone. You also could have a pinched or sliced o-ring in the oil pump OR you could have a leak coming from the gearbox as Roger said.