diff --git a/cells/fill/sky130_fd_sc_hd__fill_1.lef b/cells/fill/sky130_fd_sc_hd__fill_1.lef
index 07fab20..7e7738d 100644
--- a/cells/fill/sky130_fd_sc_hd__fill_1.lef
+++ b/cells/fill/sky130_fd_sc_hd__fill_1.lef
@@ -19,7 +19,7 @@
 BUSBITCHARS "[]" ;
 DIVIDERCHAR "/" ;
 MACRO sky130_fd_sc_hd__fill_1
-  CLASS CORE ;
+  CLASS CORE SPACER ;
   SOURCE USER ;
   ORIGIN  0.000000  0.000000 ;
   SIZE  0.460000 BY  2.720000 ;
diff --git a/cells/fill/sky130_fd_sc_hd__fill_1.magic.lef b/cells/fill/sky130_fd_sc_hd__fill_1.magic.lef
index e09aa4f..d1b67c9 100644
--- a/cells/fill/sky130_fd_sc_hd__fill_1.magic.lef
+++ b/cells/fill/sky130_fd_sc_hd__fill_1.magic.lef
@@ -22,7 +22,7 @@
   DATABASE MICRONS 200 ;
 END UNITS
 MACRO sky130_fd_sc_hd__fill_1
-  CLASS CORE ;
+  CLASS CORE SPACER ;
   FOREIGN sky130_fd_sc_hd__fill_1 ;
   ORIGIN  0.000000  0.000000 ;
   SIZE  0.460000 BY  2.720000 ;
diff --git a/cells/fill/sky130_fd_sc_hd__fill_2.lef b/cells/fill/sky130_fd_sc_hd__fill_2.lef
index 0e33726..c0e34d7 100644
--- a/cells/fill/sky130_fd_sc_hd__fill_2.lef
+++ b/cells/fill/sky130_fd_sc_hd__fill_2.lef
@@ -19,7 +19,7 @@
 BUSBITCHARS "[]" ;
 DIVIDERCHAR "/" ;
 MACRO sky130_fd_sc_hd__fill_2
-  CLASS CORE ;
+  CLASS CORE SPACER ;
   SOURCE USER ;
   ORIGIN  0.000000  0.000000 ;
   SIZE  0.920000 BY  2.720000 ;
diff --git a/cells/fill/sky130_fd_sc_hd__fill_2.magic.lef b/cells/fill/sky130_fd_sc_hd__fill_2.magic.lef
index e56a239..5595338 100644
--- a/cells/fill/sky130_fd_sc_hd__fill_2.magic.lef
+++ b/cells/fill/sky130_fd_sc_hd__fill_2.magic.lef
@@ -22,7 +22,7 @@
   DATABASE MICRONS 200 ;
 END UNITS
 MACRO sky130_fd_sc_hd__fill_2
-  CLASS CORE ;
+  CLASS CORE SPACER ;
   FOREIGN sky130_fd_sc_hd__fill_2 ;
   ORIGIN  0.000000  0.000000 ;
   SIZE  0.920000 BY  2.720000 ;
diff --git a/cells/fill/sky130_fd_sc_hd__fill_4.lef b/cells/fill/sky130_fd_sc_hd__fill_4.lef
index 93966e8..e2f44ef 100644
--- a/cells/fill/sky130_fd_sc_hd__fill_4.lef
+++ b/cells/fill/sky130_fd_sc_hd__fill_4.lef
@@ -19,7 +19,7 @@
 BUSBITCHARS "[]" ;
 DIVIDERCHAR "/" ;
 MACRO sky130_fd_sc_hd__fill_4
-  CLASS CORE ;
+  CLASS CORE SPACER ;
   SOURCE USER ;
   ORIGIN  0.000000  0.000000 ;
   SIZE  1.840000 BY  2.720000 ;
diff --git a/cells/fill/sky130_fd_sc_hd__fill_4.magic.lef b/cells/fill/sky130_fd_sc_hd__fill_4.magic.lef
index fdffb00..4493971 100644
--- a/cells/fill/sky130_fd_sc_hd__fill_4.magic.lef
+++ b/cells/fill/sky130_fd_sc_hd__fill_4.magic.lef
@@ -22,7 +22,7 @@
   DATABASE MICRONS 200 ;
 END UNITS
 MACRO sky130_fd_sc_hd__fill_4
-  CLASS CORE ;
+  CLASS CORE SPACER ;
   FOREIGN sky130_fd_sc_hd__fill_4 ;
   ORIGIN  0.000000  0.000000 ;
   SIZE  1.840000 BY  2.720000 ;
diff --git a/cells/fill/sky130_fd_sc_hd__fill_8.lef b/cells/fill/sky130_fd_sc_hd__fill_8.lef
index b3157e7..4fc8afd 100644
--- a/cells/fill/sky130_fd_sc_hd__fill_8.lef
+++ b/cells/fill/sky130_fd_sc_hd__fill_8.lef
@@ -19,7 +19,7 @@
 BUSBITCHARS "[]" ;
 DIVIDERCHAR "/" ;
 MACRO sky130_fd_sc_hd__fill_8
-  CLASS CORE ;
+  CLASS CORE SPACER ;
   SOURCE USER ;
   ORIGIN  0.000000  0.000000 ;
   SIZE  3.680000 BY  2.720000 ;
diff --git a/cells/fill/sky130_fd_sc_hd__fill_8.magic.lef b/cells/fill/sky130_fd_sc_hd__fill_8.magic.lef
index 2f75b0d..24cd3ed 100644
--- a/cells/fill/sky130_fd_sc_hd__fill_8.magic.lef
+++ b/cells/fill/sky130_fd_sc_hd__fill_8.magic.lef
@@ -22,7 +22,7 @@
   DATABASE MICRONS 200 ;
 END UNITS
 MACRO sky130_fd_sc_hd__fill_8
-  CLASS CORE ;
+  CLASS CORE SPACER ;
   FOREIGN sky130_fd_sc_hd__fill_8 ;
   ORIGIN  0.000000  0.000000 ;
   SIZE  3.680000 BY  2.720000 ;