diff --git a/entity/batch.go b/entity/batch.go
index fbe155c7..8d47c677 100644
--- a/entity/batch.go
+++ b/entity/batch.go
@@ -1,5 +1,7 @@
 package entity
 
+import "encoding/json"
+
 // BatchState defines the possible states of a batch.
 type BatchState string
 
@@ -61,3 +63,15 @@ type Batch struct {
 	// Versioning starts at 1 and is incremented for each change to the object.
 	Version int32
 }
+
+// ToBytes serializes the Batch to JSON bytes for queue message payload.
+func (b Batch) ToBytes() ([]byte, error) {
+	return json.Marshal(b)
+}
+
+// BatchFromBytes deserializes a Batch from JSON bytes.
+func BatchFromBytes(data []byte) (Batch, error) {
+	var batch Batch
+	err := json.Unmarshal(data, &batch)
+	return batch, err
+}
diff --git a/entity/batch_test.go b/entity/batch_test.go
index 084e4b21..e204b24f 100644
--- a/entity/batch_test.go
+++ b/entity/batch_test.go
@@ -4,6 +4,7 @@ import (
 	"testing"
 
 	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
 )
 
 func TestBatchState_IsTerminal(t *testing.T) {
@@ -28,3 +29,94 @@ func TestBatchState_IsTerminal(t *testing.T) {
 		})
 	}
 }
+
+func TestBatch_SerializationRoundTrip(t *testing.T) {
+	tests := []struct {
+		name  string
+		batch Batch
+	}{
+		{
+			name: "batch with single request",
+			batch: Batch{
+				ID:       "queueA/batch/1",
+				Queue:    "queueA",
+				Contains: []string{"queueA/1"},
+				State:    BatchStateCreated,
+				Version:  1,
+			},
+		},
+		{
+			name: "batch with multiple requests",
+			batch: Batch{
+				ID:       "queueB/batch/42",
+				Queue:    "queueB",
+				Contains: []string{"queueB/10", "queueB/11", "queueB/12"},
+				State:    BatchStateSpeculating,
+				Version:  3,
+			},
+		},
+		{
+			name: "batch with dependencies",
+			batch: Batch{
+				ID:       "queueA/batch/3",
+				Queue:    "queueA",
+				Contains: []string{"queueA/5"},
+				Dependencies: []map[string]interface{}{
+					{"id": "queueA/batch/1"},
+					{"id": "queueA/batch/2"},
+				},
+				State:   BatchStateCreated,
+				Version: 1,
+			},
+		},
+		{
+			name: "batch in terminal state",
+			batch: Batch{
+				ID:       "queueC/batch/99",
+				Queue:    "queueC",
+				Contains: []string{"queueC/50"},
+				State:    BatchStateSucceeded,
+				Version:  5,
+			},
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			data, err := tt.batch.ToBytes()
+			require.NoError(t, err)
+
+			deserialized, err := BatchFromBytes(data)
+			require.NoError(t, err)
+
+			assert.Equal(t, tt.batch, deserialized)
+		})
+	}
+}
+
+func TestBatchFromBytes_InvalidJSON(t *testing.T) {
+	_, err := BatchFromBytes([]byte(`{"invalid": json"}`))
+	assert.Error(t, err)
+}
+
+func TestBatchFromBytes_EmptyJSON(t *testing.T) {
+	batch, err := BatchFromBytes([]byte(`{}`))
+	require.NoError(t, err)
+
+	assert.Empty(t, batch.ID)
+	assert.Empty(t, batch.Queue)
+	assert.Nil(t, batch.Contains)
+	assert.Nil(t, batch.Dependencies)
+	assert.Equal(t, BatchStateUnknown, batch.State)
+	assert.Equal(t, int32(0), batch.Version)
+}
+
+func TestBatchFromBytes_EmptyBytes(t *testing.T) {
+	_, err := BatchFromBytes([]byte{})
+	assert.Error(t, err)
+}
+
+func TestBatchFromBytes_NilBytes(t *testing.T) {
+	_, err := BatchFromBytes(nil)
+	assert.Error(t, err)
+}
diff --git a/orchestrator/controller/batch/batch.go b/orchestrator/controller/batch/batch.go
index d880d6b5..1f6e1840 100644
--- a/orchestrator/controller/batch/batch.go
+++ b/orchestrator/controller/batch/batch.go
@@ -110,9 +110,9 @@ func (c *Controller) Process(ctx context.Context, delivery consumer.Delivery) er
 	// - Add to batch dependent DB
 
 	// Publish to speculate topic
-	if err := c.publish(ctx, consumer.TopicKeyBatched, request); err != nil {
+	if err := c.publish(ctx, consumer.TopicKeyBatched, batch); err != nil {
 		c.logger.Errorw("failed to publish output",
-			"request_id", request.ID,
+			"batch_id", batch.ID,
 			"topic_key", consumer.TopicKeyBatched,
 			"error", err,
 		)
@@ -120,8 +120,8 @@ func (c *Controller) Process(ctx context.Context, delivery consumer.Delivery) er
 		return fmt.Errorf("failed to publish to speculate: %w", err)
 	}
 
-	c.logger.Infow("published request to next stage",
-		"request_id", request.ID,
+	c.logger.Infow("published batch to next stage",
+		"batch_id", batch.ID,
 		"topic_key", consumer.TopicKeyBatched,
 	)
 
@@ -130,14 +130,14 @@ func (c *Controller) Process(ctx context.Context, delivery consumer.Delivery) er
 	return nil // Success - message will be acked
 }
 
-// publish publishes a request to the specified topic key.
-func (c *Controller) publish(ctx context.Context, key consumer.TopicKey, request entity.Request) error {
-	payload, err := request.ToBytes()
+// publish publishes a batch to the specified topic key.
+func (c *Controller) publish(ctx context.Context, key consumer.TopicKey, batch entity.Batch) error {
+	payload, err := batch.ToBytes()
 	if err != nil {
-		return fmt.Errorf("failed to serialize request: %w", err)
+		return fmt.Errorf("failed to serialize batch: %w", err)
 	}
 
-	msg := entityqueue.NewMessage(request.ID, payload, request.Queue, nil)
+	msg := entityqueue.NewMessage(batch.ID, payload, batch.Queue, nil)
 
 	q, ok := c.registry.Queue(key)
 	if !ok {