diff --git a/slycot/analysis.py b/slycot/analysis.py
index d41e2043..9542fdaa 100644
--- a/slycot/analysis.py
+++ b/slycot/analysis.py
@@ -1384,12 +1384,7 @@ def ab13bd(dico, jobn, n, m, p, A, B, C, D, tol = 0.0):
                 'D', 'ldd' + hidden, 'nq' + hidden,'tol', 'dwork' + hidden,
                 'ldwork' + hidden, 'iwarn', 'info')
     
-    a = A.copy()
-    b = B.copy()
-    c = C.copy()
-    d = D.copy()
-    
-    out = _wrapper.ab13bd(dico, jobn, n, m, p, a, b, c, d, tol)
+    out = _wrapper.ab13bd(dico, jobn, n, m, p, A, B, C, D, tol)
 
     raise_if_slycot_error(out[-2:], arg_list, ab13bd.__doc__, locals())
     return out[0]
diff --git a/slycot/src/analysis.pyf b/slycot/src/analysis.pyf
index c306b114..663c4747 100644
--- a/slycot/src/analysis.pyf
+++ b/slycot/src/analysis.pyf
@@ -307,13 +307,13 @@ function ab13bd(dico,jobn,n,m,p,a,lda,b,ldb,c,ldc,d,ldd,nq,tol,dwork,ldwork,iwar
     integer check(n>=0) :: n
     integer check(m>=0) :: m
     integer check(p>=0) :: p
-    double precision dimension(n,n),depend(n) :: a
+    double precision intent(in,out,copy), dimension(n,n),depend(n) :: a
     integer intent(hide),depend(a) :: lda = shape(a,0)
-    double precision dimension(n,m),depend(n,m) :: b
+    double precision intent(in,out,copy), dimension(n,m),depend(n,m) :: b
     integer intent(hide),depend(b) :: ldb = shape(b,0)
-    double precision dimension(p,n),depend(n,p) :: c
+    double precision intent(in,out,copy), dimension(p,n),depend(n,p) :: c
     integer intent(hide),depend(c) :: ldc = shape(c,0)
-    double precision dimension(p,m),depend(m,p) :: d
+    double precision intent(in,out,copy), dimension(p,m),depend(m,p) :: d
     integer intent(hide),depend(d) :: ldd = shape(d,0)
     integer intent(out) :: nq
     double precision :: tol