Title: Invariants of Binary Forms Modulo Two Authors: Larry Smith (AG-Invariantentheorie) and R.E. Stong (University of Virginia) Name of the .PDF file: binary.pdf } We examine the invariant theory of binary bilinear forms over the field $\F_2$ of two elements that arises in the classification of (standardly graded) Poincar\'e duality algebras with two algebra generators over the field $\F_2$ of two elements. We compute the corresponding ring of invariants and find seperating invariants for the orbit space.