That's true, Ed. During his career Dylan has written some songs that he more or less "donated" to various musical friends to do as cover tunes and seldom performed himself. Or else it just happened that way in a passive sense. Some examples:

Farewell Angelina - a Joan Baez standard
Love Is Just a Four Letter Word - another Joan Baez standard
Seven Days - Ron Wood cover
This Wheel's On Fire - The Band
I Shall Be Released - first covered by The Band, I think, but Dylan has also played it a fair bit in concerts
The Mighty Quinn - barely ever performed by Dylan, but Manfred Mann had a hit with it