diff --git a/engine/verifier/src/orm/add_remove_triples.rs b/engine/verifier/src/orm/add_remove_triples.rs
index a30c8b1..7adc46b 100644
--- a/engine/verifier/src/orm/add_remove_triples.rs
+++ b/engine/verifier/src/orm/add_remove_triples.rs
@@ -44,6 +44,7 @@ pub fn add_remove_triples(
                     tracked_predicates: HashMap::new(),
                     parents: HashMap::new(),
                     valid: OrmTrackedSubjectValidity::Pending,
+                    prev_valid: OrmTrackedSubjectValidity::Pending,
                     subject_iri: subject_iri.to_string(),
                     shape: shape.clone(),
                 }))
diff --git a/engine/verifier/src/orm/mod.rs b/engine/verifier/src/orm/mod.rs
index 4ca3e27..0942532 100644
--- a/engine/verifier/src/orm/mod.rs
+++ b/engine/verifier/src/orm/mod.rs
@@ -257,24 +257,9 @@ impl Verifier {
                         log_debug!("not applying triples again for subject {subject_iri}");
                     }
 
-                    let validity = {
-                        let tracked_subject_opt = orm_subscription
-                            .tracked_subjects
-                            .get(*subject_iri)
-                            .and_then(|m| m.get(&shape.iri));
-                        let Some(tracked_subject) = tracked_subject_opt else {
-                            continue;
-                        }; // skip if missing
-                        tracked_subject.read().unwrap().valid.clone()
-                    };
-
                     // Validate the subject.
-                    let need_eval = Self::update_subject_validity(
-                        change,
-                        &shape,
-                        &mut orm_subscription,
-                        validity,
-                    );
+                    let need_eval =
+                        Self::update_subject_validity(change, &shape, &mut orm_subscription);
 
                     // We add the need_eval to be processed next after loop.
                     // Filter out subjects already in the validation stack to prevent double evaluation.
diff --git a/engine/verifier/src/orm/types.rs b/engine/verifier/src/orm/types.rs
index ac8721d..8d156c7 100644
--- a/engine/verifier/src/orm/types.rs
+++ b/engine/verifier/src/orm/types.rs
@@ -23,8 +23,11 @@ pub struct OrmTrackedSubject {
     /// If this is a nested subject, this records the parents
     /// and if they are currently tracking this subject.
     pub parents: HashMap<String, Arc<RwLock<OrmTrackedSubject>>>,
-    /// Validity. When untracked, triple updates are not processed here.
+    /// Validity. When untracked, triple updates are not processed for this tracked subject.
     pub valid: OrmTrackedSubjectValidity,
+    /// Previous validity. Used for validation and creating JSON Patch diffs from changes.
+    pub prev_valid: OrmTrackedSubjectValidity,
+    /// Subject IRI
     pub subject_iri: String,
     /// The shape for which the predicates are tracked.
     pub shape: Arc<OrmSchemaShape>,
diff --git a/engine/verifier/src/orm/validation.rs b/engine/verifier/src/orm/validation.rs
index 94754fd..fc41cc2 100644
--- a/engine/verifier/src/orm/validation.rs
+++ b/engine/verifier/src/orm/validation.rs
@@ -22,7 +22,6 @@ impl Verifier {
         s_change: &OrmTrackedSubjectChange,
         shape: &OrmSchemaShape,
         orm_subscription: &mut OrmSubscription,
-        previous_validity: OrmTrackedSubjectValidity,
     ) -> Vec<(SubjectIri, ShapeIri, NeedsFetchBool)> {
         let tracked_subjects = &mut orm_subscription.tracked_subjects;
 
@@ -33,6 +32,9 @@ impl Verifier {
             return vec![];
         };
         let mut tracked_subject = tracked_subject.write().unwrap();
+        let previous_validity = tracked_subject.prev_valid.clone();
+        tracked_subject.prev_valid = tracked_subject.valid.clone();
+
         // Keep track of objects that need to be validated against a shape to fetch and validate.
         let mut need_evaluation: Vec<(String, String, bool)> = vec![];