diff --git a/src/option.c b/src/option.c
index e9c6a50..3050dbc 100644
--- a/src/option.c
+++ b/src/option.c
@@ -2135,10 +2135,14 @@
 	    ((flags & P_VI_DEF) || cp_val) ? VI_DEFAULT : VIM_DEFAULT];
     else if (nextchar == '<')
     {
-	// For 'undolevels' NO_LOCAL_UNDOLEVEL means to
-	// use the global value.
 	if ((long *)varp == &curbuf->b_p_ul && opt_flags == OPT_LOCAL)
+	    // for 'undolevels' NO_LOCAL_UNDOLEVEL means using the global value
 	    value = NO_LOCAL_UNDOLEVEL;
+	else if (opt_flags == OPT_LOCAL
+		    && ((long *)varp == &curwin->w_p_siso
+		     || (long *)varp == &curwin->w_p_so))
+	    // for 'scrolloff'/'sidescrolloff' -1 means using the global value
+	    value = -1;
 	else
 	    value = *(long *)get_varp_scope(&(options[opt_idx]), OPT_GLOBAL);
     }
diff --git a/src/testdir/test_options.vim b/src/testdir/test_options.vim
index 015ecc1..0de5e25 100644
--- a/src/testdir/test_options.vim
+++ b/src/testdir/test_options.vim
@@ -954,12 +954,16 @@
   wincmd w
   call assert_equal(5, &so)
   wincmd w
+  call assert_equal(3, &so)
   setlocal so<
   call assert_equal(5, &so)
+  setglob so=8
+  call assert_equal(8, &so)
+  call assert_equal(-1, &l:so)
   setlocal so=0
   call assert_equal(0, &so)
   setlocal so=-1
-  call assert_equal(5, &so)
+  call assert_equal(8, &so)
 
   call assert_equal(7, &siso)
   setlocal siso=3
@@ -967,12 +971,16 @@
   wincmd w
   call assert_equal(7, &siso)
   wincmd w
+  call assert_equal(3, &siso)
   setlocal siso<
   call assert_equal(7, &siso)
+  setglob siso=4
+  call assert_equal(4, &siso)
+  call assert_equal(-1, &l:siso)
   setlocal siso=0
   call assert_equal(0, &siso)
   setlocal siso=-1
-  call assert_equal(7, &siso)
+  call assert_equal(4, &siso)
 
   close
   set so&
diff --git a/src/version.c b/src/version.c
index 316649f..bc2b0b5 100644
--- a/src/version.c
+++ b/src/version.c
@@ -696,6 +696,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1670,
+/**/
     1669,
 /**/
     1668,