  Given a real symmetric $n\times n$ matrix, the sepr-sequence $t_1\cdots t_n$
records information about the existence of principal minors of each order that
are positive, negative, or zero. This paper extends the notion of the
sepr-sequence to matrices whose entries are of prescribed signs, that is, to
sign patterns. A sufficient condition is given for a sign pattern to have a
unique sepr-sequence, and it is conjectured to be necessary. The sepr-sequences
of sign semi-stable patterns are shown to be well-structured; in some special
circumstances, the sepr-sequence is enough to guarantee the sign pattern being
sign semi-stable. In alignment with previous work on symmetric matrices, the
sepr-sequences for sign patterns realized by symmetric nonnegative matrices of
orders two and three are characterized.
