diff --git a/core/src/main/kotlin/net/corda/core/utilities/FlowSafeSubject.kt b/node/src/main/kotlin/net/corda/node/internal/FlowSafeSubject.kt
similarity index 97%
rename from core/src/main/kotlin/net/corda/core/utilities/FlowSafeSubject.kt
rename to node/src/main/kotlin/net/corda/node/internal/FlowSafeSubject.kt
index 4a7077e6aa..5336298a03 100644
--- a/core/src/main/kotlin/net/corda/core/utilities/FlowSafeSubject.kt
+++ b/node/src/main/kotlin/net/corda/node/internal/FlowSafeSubject.kt
@@ -1,4 +1,4 @@
-package net.corda.core.utilities
+package net.corda.node.internal
 
 import net.corda.core.internal.FlowSafeSubscriber
 import net.corda.core.internal.VisibleForTesting
diff --git a/node/src/main/kotlin/net/corda/node/services/vault/NodeVaultService.kt b/node/src/main/kotlin/net/corda/node/services/vault/NodeVaultService.kt
index 973ca5ba18..ac0b5e7cb2 100644
--- a/node/src/main/kotlin/net/corda/node/services/vault/NodeVaultService.kt
+++ b/node/src/main/kotlin/net/corda/node/services/vault/NodeVaultService.kt
@@ -18,6 +18,8 @@ import net.corda.core.schemas.PersistentStateRef
 import net.corda.core.serialization.SingletonSerializeAsToken
 import net.corda.core.transactions.*
 import net.corda.core.utilities.*
+import net.corda.node.internal.FlowSafeSubject
+import net.corda.node.internal.PreventSubscriptionsSubject
 import net.corda.node.services.api.SchemaService
 import net.corda.node.services.api.VaultServiceInternal
 import net.corda.node.services.schema.PersistentStateService
diff --git a/node/src/test/kotlin/net/corda/node/utilities/ObservablesTests.kt b/node/src/test/kotlin/net/corda/node/utilities/ObservablesTests.kt
index db2e6251db..0ddfe58164 100644
--- a/node/src/test/kotlin/net/corda/node/utilities/ObservablesTests.kt
+++ b/node/src/test/kotlin/net/corda/node/utilities/ObservablesTests.kt
@@ -3,7 +3,7 @@ package net.corda.node.utilities
 import com.google.common.util.concurrent.SettableFuture
 import net.corda.core.internal.bufferUntilSubscribed
 import net.corda.core.internal.tee
-import net.corda.core.utilities.FlowSafeSubject
+import net.corda.node.internal.FlowSafeSubject
 import net.corda.core.internal.FlowSafeSubscriber
 import net.corda.core.internal.OnNextFailedException
 import net.corda.nodeapi.internal.persistence.*