Continuity mistake: When Adrian stamps "denied" onto Boyle's insurance claim form, there's blank spots where there wasn't enough ink on the stamp (which would happen because he had the stamp in his pocket for a while). But then when he says "denied" and holds up the form, "denied" is all filled in fully. Also, the red border is lighter and the location has shifted down.
Caperberries and a Fat Detective - S3-E17
Continuity mistake: When they're on the phone with Adam, between shots the phone switches hands.
Something Ricked This Way Comes - S1-E9
Continuity mistake: When Rick, Jerry and Beth are eating pancakes, Jerry has his fork in his, but when Morty walks into the room and Jerry mentions science fairs are a father/son thing, Jerry's fork is suddenly on the table beside the knife. A further two shots after, the fork is suddenly back in the pancakes.