diff --git a/src/lisp/regression-tests/geometry.lisp b/src/lisp/regression-tests/geometry.lisp
new file mode 100644
index 00000000..0567845e
--- /dev/null
+++ b/src/lisp/regression-tests/geometry.lisp
@@ -0,0 +1,14 @@
+(in-package #:clasp-tests)
+
+
+(test-true sign-dihedral (> (geom:calculate-dihedral (geom:vec -1.0 1.0 0.0) (geom:vec -1.0 0.0 0.0) (geom:vec 0.0 0.0 0.0) (geom:vec 0.0 0.0 1.0)) 0.0))
+(test-true sign-inv-dihedral (< (geom:vz (geom:point-from-stub-and-internal-coordinates (geom:make-matrix t) 1.0 (/ pi 2.0) (/ pi 2.0))) 0.0))
+(test-true sign-other-dihedral (> (geom:vz (geom:build-using-bond-angle-dihedral
+                                            1.0 (geom:vec 0.0 0.0 0.0)
+                                            (/ pi 2.0) (geom:vec -1.0 0.0 0.0)
+                                            (/ pi 2.0) (geom:vec -1.0 1.0 0.0)))
+                                  0.0))
+(test-true sign-plane-vector-angle1 (< (geom:plane-vector-angle  1.0  1.0) 0.0))
+(test-true sign-plane-vector-angle2 (< (geom:plane-vector-angle -1.0  1.0) 0.0))
+(test-true sign-plane-vector-angle3 (> (geom:plane-vector-angle  1.0 -1.0) 0.0))
+(test-true sign-plane-vector-angle4 (> (geom:plane-vector-angle -1.0 -1.0) 0.0))