diff --git a/src/plugins/streamers/lefdef/db_plugin/dbDEFImporter.cc b/src/plugins/streamers/lefdef/db_plugin/dbDEFImporter.cc
index a47f99d32..b07a347b0 100644
--- a/src/plugins/streamers/lefdef/db_plugin/dbDEFImporter.cc
+++ b/src/plugins/streamers/lefdef/db_plugin/dbDEFImporter.cc
@@ -749,7 +749,12 @@ DEFImporter::read_single_net (std::string &nondefaultrule, Layout &layout, db::C
         }
 
         std::map<std::string, ViaDesc>::const_iterator vd = m_via_desc.find (vn);
-        if (vd != m_via_desc.end () && ! pts.empty ()) {
+
+        if (vd == m_via_desc.end ()) {
+
+          warn (tl::to_string (tr ("Invalid via name: ")) + vn);
+
+        } else if (! pts.empty ()) {
 
           //  For the via, the masks are encoded in a three-digit number (<mask-top> <mask-cut> <mask_bottom>)
           unsigned int mask_top = (mask / 100) % 10;
diff --git a/src/plugins/streamers/lefdef/unit_tests/dbLEFDEFImportTests.cc b/src/plugins/streamers/lefdef/unit_tests/dbLEFDEFImportTests.cc
index fb786413f..f430e4829 100644
--- a/src/plugins/streamers/lefdef/unit_tests/dbLEFDEFImportTests.cc
+++ b/src/plugins/streamers/lefdef/unit_tests/dbLEFDEFImportTests.cc
@@ -898,6 +898,21 @@ TEST(132_issue1307_pin_names)
   run_test (_this, "issue-1307c", "lef:in.lef+def:in.def", "au.oas", opt, false);
 }
 
+/*
+TODO: need to clarify first, if invalid via specs should be errors
+TEST(133_unknown_vias_are_errors)
+{
+  db::LEFDEFReaderOptions opt = default_options ();
+
+  try {
+    run_test (_this, "invalid_via", "lef:tech.lef+def:comp_invalid_via.def", "au.oas", opt, false);
+    EXPECT_EQ (true, false);
+  } catch (db::LEFDEFReaderException &ex) {
+    EXPECT_EQ (ex.msg ().find ("Invalid via name"), size_t (0));
+  }
+}
+*/
+
 TEST(200_lefdef_plugin)
 {
   db::Layout ly;
diff --git a/testdata/lefdef/invalid_via/comp_invalid_via.def b/testdata/lefdef/invalid_via/comp_invalid_via.def
new file mode 100644
index 000000000..1eb475daf
--- /dev/null
+++ b/testdata/lefdef/invalid_via/comp_invalid_via.def
@@ -0,0 +1,16 @@
+VERSION 5.8 ;
+DIVIDERCHAR "/" ;
+BUSBITCHARS "[]" ;
+DESIGN comp_invalid_via ;
+UNITS DISTANCE MICRONS 1000 ;
+DIEAREA ( 0 0 ) ( 10000 2000 ) ;
+
+SPECIALNETS 2 ;
+    - VGND ( PIN VGND ) ( * VNB ) ( * VGND ) + USE GROUND
+      + ROUTED met1 480 + SHAPE FOLLOWPIN ( 0 1000 ) ( 2000 1000 )
+      NEW met1 0 + SHAPE STRIPE ( 2000 1000 ) via1
+      + ROUTED met2 480 + SHAPE FOLLOWPIN ( 2000 1000 ) ( 4000 1000 )
+      NEW met2 0 + SHAPE STRIPE ( 4000 1000 ) invalid_via ;
+END SPECIALNETS
+END DESIGN
+
diff --git a/testdata/lefdef/invalid_via/tech.lef b/testdata/lefdef/invalid_via/tech.lef
new file mode 100644
index 000000000..cae5bcd54
--- /dev/null
+++ b/testdata/lefdef/invalid_via/tech.lef
@@ -0,0 +1,89 @@
+
+VERSION 5.7 ;
+
+BUSBITCHARS "[]" ;
+DIVIDERCHAR "/" ;
+USEMINSPACING OBS OFF ;
+
+UNITS
+  DATABASE MICRONS 1000 ;
+END UNITS
+
+MANUFACTURINGGRID 0.005 ;
+
+LAYER met1
+  TYPE ROUTING ;
+  DIRECTION HORIZONTAL ;
+  PITCH 0.34 ;
+  OFFSET 0.17 ;
+  WIDTH 0.14 ;
+END met1
+
+LAYER via
+  TYPE CUT ;
+  WIDTH 0.15 ;
+  SPACING 0.17 ;
+END via
+
+LAYER met2
+  TYPE ROUTING ;
+  DIRECTION VERTICAL ;
+  PITCH 0.46 ;
+  OFFSET 0.23 ;
+  WIDTH 0.14 ; 
+END met2
+
+LAYER via2
+  TYPE CUT ;
+  WIDTH 0.2 ; 
+  SPACING 0.2 ;
+END via2
+
+LAYER met3
+  TYPE ROUTING ;
+  DIRECTION HORIZONTAL ;
+  PITCH 0.68 ;
+  OFFSET 0.34 ;
+  WIDTH 0.3 ; 
+END met3
+
+VIA via1 DEFAULT
+  LAYER via ;
+  RECT -0.075 -0.075 0.075 0.075 ;
+  LAYER met1 ;
+  RECT -0.16 -0.24 0.16 0.24 ;
+  LAYER met2 ;
+  RECT -0.13 -0.24 0.13 0.24 ;
+END via1
+
+VIARULE M1M2_PR GENERATE
+  LAYER met1 ;
+  ENCLOSURE 0.085 0.055 ;
+  LAYER met2 ;
+  ENCLOSURE 0.055 0.085 ;
+  LAYER via ;
+  RECT -0.075 -0.075 0.075 0.075 ;
+  SPACING 0.32 BY 0.32 ;
+END M1M2_PR
+
+VIA via2 DEFAULT
+  LAYER via2 ;
+  RECT -0.1 -0.1 0.1 0.1 ;
+  LAYER met2 ;
+  RECT -0.14 -0.24 0.14 0.24 ;
+  LAYER met3 ;
+  RECT -0.165 -0.165 0.165 0.165 ;
+END via2
+
+VIARULE M2M3_PR GENERATE
+  LAYER met2 ;
+  ENCLOSURE 0.04 0.085 ;
+  LAYER met3 ;
+  ENCLOSURE 0.065 0.065 ;
+  LAYER via2 ;
+  RECT -0.1 -0.1 0.1 0.1 ;
+  SPACING 0.4 BY 0.4 ;
+END M2M3_PR
+
+END LIBRARY
+ 
diff --git a/testdata/lefdef/multi_def/au.oas b/testdata/lefdef/multi_def/au.oas
index 3b6e66367..4f1002177 100644
Binary files a/testdata/lefdef/multi_def/au.oas and b/testdata/lefdef/multi_def/au.oas differ