diff --git a/sky130/magic/sky130.tech b/sky130/magic/sky130.tech
index 9e288ad..bfc9635 100644
--- a/sky130/magic/sky130.tech
+++ b/sky130/magic/sky130.tech
@@ -2586,6 +2586,7 @@
 
  # Always force nwell under pfet (nwell encloses pdiff by 0.18)
  layer nwell pfetarea
+ and-not COREID
  grow 180
 
  # Copy mvpdiff areas up for contact checks