Why is my chainsaw leaking oil?

POSSIBLE REASONS

• Bar and chain oil is stickier than regular motor oil, so it stays on the chain longer which allows oil accumulates around the guide bar and grooves which settles when the chainsaw it put away.
• When storing if the chainsaw is tilted in an angle which can leak from the valve.
• Air pressure built up in the oil tank. 

RECOMMENDATIONS 

• Always empty oil tank when finished cutting. When storing your chainsaw for days, weeks, or more, its best to empty the oil tank. 
• Release any pressure built up by opening the cap can prevent it leaking.
• Store the chainsaw so the guide bar is neutral or without the guide bar facing down.