diff --git a/core/src/main/java/org/dcache/nfs/v4/OperationOPEN.java b/core/src/main/java/org/dcache/nfs/v4/OperationOPEN.java
index c455c962e..c32717243 100644
--- a/core/src/main/java/org/dcache/nfs/v4/OperationOPEN.java
+++ b/core/src/main/java/org/dcache/nfs/v4/OperationOPEN.java
@@ -94,7 +94,7 @@ public void process(CompoundContext context, nfs_resop4 result) throws ChimeraNF
 
             case open_claim_type4.CLAIM_NULL:
 
-                if (client.needReclaim() && context.getStateHandler().isGracePeriod()) {
+                if (client.needReclaim() || context.getStateHandler().isGracePeriod()) {
                     throw new GraceException();
                 }