There are about as many opinions about the nature of a Sasquatch thumb as there are Sasquatch researchers. The Patterson film has a lot to say about the thumb if a person can stabilize that area so that its subtle movements can be observed. This has been done in the clips below. Notice the left arm. It has been held steady through film stabilization and the thumb can indeed be seen to move on the left hand. It has every appearance of an opposable thumb.