  Suppose that $G$ is a simple, vertex-labeled graph and that $S$ is a
multiset. Then if there exists a one-to-one mapping between the elements of $S$
and the vertices of $G$, such that edges in $G$ exist if and only if the
absolute difference of the corresponding vertex labels exist in $S$, then $G$
is an \emph{autograph}, and $S$ is a \emph{signature} for $G$. While it is
known that many common families are graphs are autographs, and that infinitely
many graphs are not autographs, a non-autograph has never been exhibited. In
this paper, we identify the smallest non-autograph: a graph with 6 vertices and
11 edges. Furthermore, we demonstrate that the infinite family of graphs on $n$
vertices consisting of the complement of two non-intersecting cycles contains
only non-autographs for $n \geq 8$.
