diff --git a/src/plugins/streamers/lefdef/db_plugin/dbLEFDEFImporter.cc b/src/plugins/streamers/lefdef/db_plugin/dbLEFDEFImporter.cc
index 55a4e7ecc..a60e37a89 100644
--- a/src/plugins/streamers/lefdef/db_plugin/dbLEFDEFImporter.cc
+++ b/src/plugins/streamers/lefdef/db_plugin/dbLEFDEFImporter.cc
@@ -656,38 +656,44 @@ LEFDEFImporter::create_generated_via (std::vector<db::Polygon> &bottom,
   top.push_back (db::Polygon (via_box.enlarged (te).moved (to)));
 
   const char *p = pattern.c_str ();
-  int rp = 0;
+  int rp = pattern.empty () ? -1 : 0;
   const char *p0 = p, *p1 = p;
 
   for (int r = 0; r < rows; ++r) {
 
-    if (rp == 0 && *p) {
+    if (rp == 0) {
 
-      //  read a new row specification
-      rp = 0;
-      while (*p && is_hex_digit (*p)) {
-        rp = (rp * 16) + hex_value (*p++);
-      }
-      if (*p == '_') {
-        ++p;
-      }
-
-      p0 = p;
       if (*p) {
-        while (*p && (is_hex_digit (*p) || toupper (*p) == 'R')) {
+
+        //  read a new row specification
+        rp = 0;
+        while (*p && is_hex_digit (*p)) {
+          rp = (rp * 16) + hex_value (*p++);
+        }
+        if (*p == '_') {
           ++p;
         }
-      }
-      p1 = p;
-      if (*p == '_') {
-        ++p;
+
+        p0 = p;
+        if (*p) {
+          while (*p && (is_hex_digit (*p) || toupper (*p) == 'R')) {
+            ++p;
+          }
+        }
+        p1 = p;
+        if (*p == '_') {
+          ++p;
+        }
+
       }
 
     }
 
-    if (rp > 0) {
+    if (rp != 0) {
 
-      --rp;
+      if (rp > 0) {
+        --rp;
+      }
 
       const char *pp = p0;
       unsigned int d = 0;
diff --git a/src/plugins/streamers/lefdef/unit_tests/dbLEFDEFImport.cc b/src/plugins/streamers/lefdef/unit_tests/dbLEFDEFImport.cc
index 79f06c647..92e3eb883 100644
--- a/src/plugins/streamers/lefdef/unit_tests/dbLEFDEFImport.cc
+++ b/src/plugins/streamers/lefdef/unit_tests/dbLEFDEFImport.cc
@@ -260,3 +260,8 @@ TEST(22)
   run_test (_this, "issue-489b", "lef:in_tech.lef+lef:in.lef", "au.oas.gz", opt, false);
 }
 
+TEST(23)
+{
+  run_test (_this, "issue-517", "def:in.def", "au.oas.gz", default_options (), false);
+}
+
diff --git a/testdata/lefdef/issue-517/au.oas.gz b/testdata/lefdef/issue-517/au.oas.gz
new file mode 100644
index 000000000..429872948
Binary files /dev/null and b/testdata/lefdef/issue-517/au.oas.gz differ
diff --git a/testdata/lefdef/issue-517/in.def b/testdata/lefdef/issue-517/in.def
new file mode 100644
index 000000000..fcb5a4789
--- /dev/null
+++ b/testdata/lefdef/issue-517/in.def
@@ -0,0 +1,29 @@
+
+VERSION 5.6 ;
+NAMESCASESENSITIVE ON ;
+DIVIDERCHAR "/" ;
+BUSBITCHARS "<>" ;
+DESIGN SMALL ;
+UNITS DISTANCE MICRONS 100 ;
+
+DIEAREA ( -30 -30 ) ( 1030 1030 ) ;
+
+VIAS 1 ;
+- via1_960x340
++ VIARULE Via1Array-0
+  + CUTSIZE 140 140
+  + LAYERS metal1 via1 metal2 
+  + CUTSPACING 160 160
+  + ENCLOSURE 110 100 110 100
+  + ROWCOL 1 3
+;
+END VIAS
+
+SPECIALNETS 1 ;
+- VDD ( * VDD )
++ ROUTED metal1 0 + SHAPE STRIPE ( 500 500 ) via1_960x340
++ USE POWER ;
+END SPECIALNETS
+
+END DESIGN
+