diff --git a/codex-plonky2-circuits/benches/safe_circuit.rs b/codex-plonky2-circuits/benches/safe_circuit.rs
index 1fdff3f..8ae9b00 100644
--- a/codex-plonky2-circuits/benches/safe_circuit.rs
+++ b/codex-plonky2-circuits/benches/safe_circuit.rs
@@ -94,7 +94,7 @@ fn build_circuit<F, C, const D: usize, H>(
     // For each proof, create targets, add constraints, and assign witnesses
     for &leaf_index in leaf_indices.iter() {
         // Build the circuit for each proof
-        let mut targets = circuit_instance.build_circuit(&mut builder);
+        let (mut targets, _root) = circuit_instance.build_circuit(&mut builder);
 
         // Assign witnesses for each proof
         circuit_instance.assign_witness(&mut pw, &mut targets, leaf_index)?;
diff --git a/codex-plonky2-circuits/src/circuits/safe_tree_circuit.rs b/codex-plonky2-circuits/src/circuits/safe_tree_circuit.rs
index 5ccb2cc..c7d5af9 100644
--- a/codex-plonky2-circuits/src/circuits/safe_tree_circuit.rs
+++ b/codex-plonky2-circuits/src/circuits/safe_tree_circuit.rs
@@ -66,7 +66,7 @@ impl<
     pub fn build_circuit(
         &mut self,
         builder: &mut CircuitBuilder::<F, D>
-    ) -> MerkleTreeTargets<F, C, D, H>{
+    ) -> (MerkleTreeTargets<F, C, { D }, H>, HashOutTarget) {
         // Retrieve tree depth
         let depth = self.tree.depth();
 
@@ -94,10 +94,10 @@ impl<
         };
 
         // Add Merkle proof verification constraints to the circuit
-        Self::reconstruct_merkle_root_circuit(builder, &mut targets);
+        let expected_root_target = Self::reconstruct_merkle_root_circuit(builder, &mut targets);
 
         // Return MerkleTreeTargets
-        targets
+        (targets, expected_root_target)
     }
 
     /// assign the witness values in the circuit targets
@@ -268,7 +268,7 @@ mod tests {
             tree: tree.clone(),
             _phantom: PhantomData,
         };
-        let mut targets = circuit_instance.build_circuit(&mut builder);
+        let (mut targets, expected_root_target) = circuit_instance.build_circuit(&mut builder);
 
         // create a PartialWitness and assign
         let mut pw = PartialWitness::new();
@@ -324,7 +324,7 @@ mod tests {
             tree: tree.clone(),
             _phantom: PhantomData,
         };
-        let mut targets = circuit_instance.build_circuit(&mut builder);
+        let (mut targets, expected_root_target) = circuit_instance.build_circuit(&mut builder);
 
         let data = builder.build::<C>();
 
diff --git a/codex-plonky2-circuits/src/circuits/sample_cells.rs b/codex-plonky2-circuits/src/circuits/sample_cells.rs
index af7c519..aa565c7 100644
--- a/codex-plonky2-circuits/src/circuits/sample_cells.rs
+++ b/codex-plonky2-circuits/src/circuits/sample_cells.rs
@@ -7,7 +7,7 @@
 
 use anyhow::Result;
 use plonky2::field::extension::Extendable;
-use plonky2::hash::hash_types::{HashOut, RichField};
+use plonky2::hash::hash_types::{HashOut, HashOutTarget, NUM_HASH_OUT_ELTS, RichField};
 use plonky2::iop::target::{BoolTarget, Target};
 use plonky2::iop::witness::{PartialWitness, WitnessWrite, Witness};
 use plonky2::plonk::circuit_builder::CircuitBuilder;
@@ -205,13 +205,15 @@ impl<
 
 //------- single cell struct ------
 
-#[derive(Clone, Debug, Eq, PartialEq)]
+#[derive(Clone)]
 pub struct DatasetTargets<
     F: RichField + Extendable<D> + Poseidon2,
     C: GenericConfig<D, F = F>,
     const D: usize,
     H: Hasher<F> + AlgebraicHasher<F>,
 > {
+    pub dataset_proof: MerkleTreeTargets<F, C, D, H>,
+    pub dataset_root: HashOutTarget,
     pub slot_proofs: Vec<SingleCellTargets<F, C, D, H>>,
 
     _phantom: PhantomData<(C,H)>,
@@ -231,6 +233,16 @@ impl<
         builder: &mut CircuitBuilder::<F, D>,
     )-> DatasetTargets<F,C,D,H>{
 
+        let (dataset_proof, dataset_root_target) = self.tree.build_circuit(builder);
+
+        // expected Merkle root
+        let dataset_expected_root = builder.add_virtual_hash();
+
+        // check equality with expected root
+        for i in 0..NUM_HASH_OUT_ELTS {
+            builder.connect(dataset_expected_root.elements[i], dataset_root_target.elements[i]);
+        }
+
         let mut slot_proofs =vec![];
         for i in 0..N_SAMPLES{
             let proof_i = SlotTreeCircuit::<F,C,D,H>::prove_single_cell(builder);
@@ -238,6 +250,8 @@ impl<
         }
 
         DatasetTargets::<F,C,D,H>{
+            dataset_proof,
+            dataset_root: dataset_expected_root,
             slot_proofs,
             _phantom: Default::default(),
         }
@@ -252,9 +266,21 @@ impl<
         slot_index:usize,
         entropy:usize,
     ){
+        // assign witness for dataset level target (proving slot root is in dataset tree)
+        self.tree.assign_witness(pw,&mut targets.dataset_proof,slot_index);
+
+        // assign the expected Merkle root of dataset to the target
+        let expected_root = self.tree.tree.root().unwrap();
+        let expected_root_hash_out = expected_root.to_vec();
+        for j in 0..expected_root_hash_out.len() {
+            pw.set_target(targets.dataset_root.elements[j], expected_root_hash_out[j]);
+        }
+
+        // the sampled slot
         let slot = &self.slot_trees[slot_index];
         let slot_root = slot.tree.tree.root().unwrap();
 
+        // do the sample N times
         for i in 0..N_SAMPLES {
             let cell_index_bits = calculate_cell_index_bits(entropy, slot_root, i);
             let cell_index = bits_le_padded_to_usize(&cell_index_bits);