Here are three signed contracts between The Doors and Elektra Records. As you can see, two of these are identical pages from an October 1968 contract. The other is a page from a February 1970 contract. Although the signatures are all clearly different, I find them to be very similar in appearance.
I'd like to point out that the other signature on each of these contracts is that of Elektra President Jac Holzman. On each of the two 1968 contracts, Holzman has signed above Lawrence Harris' printed name. Harris was also an Elektra executive at that time.
A few things that I find particularly unusual in comparing the signatures are the second "r" and second "o" in "Morrison", and the "n" in "John."