diff --git a/claim/result.go b/claim/result.go
index ef8fce07..6e44a7ca 100644
--- a/claim/result.go
+++ b/claim/result.go
@@ -100,15 +100,13 @@ func (r Results) Swap(i, j int) {
 // OutputMetadata is the output metadata from an operation.
 // Any metadata can be stored, however this provides methods
 // for safely querying and retrieving well-known metadata.
-type OutputMetadata map[string]interface{}
+type OutputMetadata map[string]map[string]string
 
 // GetMetadata for the specified output and key.
 func (o OutputMetadata) GetMetadata(outputName string, metadataKey string) (string, bool) {
 	if output, ok := o[outputName]; ok {
-		if outputMetadata, ok := output.(map[string]string); ok {
-			if value, ok := outputMetadata[metadataKey]; ok {
-				return value, true
-			}
+		if value, ok := output[metadataKey]; ok {
+			return value, true
 		}
 	}
 
@@ -122,20 +120,15 @@ func (o *OutputMetadata) SetMetadata(outputName string, metadataKey string, valu
 	}
 	metadata := *o
 
-	output, ok := metadata[outputName]
+	outputMetadata, ok := metadata[outputName]
 	if !ok {
-		output = map[string]string{
+		outputMetadata = map[string]string{
 			metadataKey: value,
 		}
-		metadata[outputName] = output
+		metadata[outputName] = outputMetadata
 		return nil
 	}
 
-	outputMetadata, ok := output.(map[string]string)
-	if !ok {
-		return errors.Errorf("cannot set the claim result's OutputMetadata[%s][%s] because it is not type map[string]string but %T", outputName, metadataKey, output)
-	}
-
 	outputMetadata[metadataKey] = value
 	return nil
 }
diff --git a/claim/result_test.go b/claim/result_test.go
index 79f3e2a1..4b47679b 100644
--- a/claim/result_test.go
+++ b/claim/result_test.go
@@ -1,6 +1,8 @@
 package claim
 
 import (
+	"encoding/json"
+	"io/ioutil"
 	"sort"
 	"testing"
 
@@ -99,16 +101,6 @@ func TestResultOutputs_SetMetadata(t *testing.T) {
 		require.NoError(t, err, "SetMetadata failed")
 		assert.Equal(t, wantoutputs, outputs, "SetMetadata did not produce the expected structure")
 	})
-
-	t.Run("existing invalid structure", func(t *testing.T) {
-		outputs := OutputMetadata{
-			outputName: map[string]interface{}{
-				metadataKey: struct{}{},
-			},
-		}
-		err := outputs.SetMetadata(outputName, metadataKey, metadataValue)
-		require.EqualError(t, err, "cannot set the claim result's OutputMetadata[test1][so-meta] because it is not type map[string]string but map[string]interface {}")
-	})
 }
 
 func TestResultOutputs_GetMetadata(t *testing.T) {
@@ -144,19 +136,6 @@ func TestResultOutputs_GetMetadata(t *testing.T) {
 		require.False(t, ok, "GetMetadata should report that it did not find the value")
 		assert.Empty(t, gotValue, "GetMetadata should return an empty value when one isn't found")
 	})
-
-	t.Run("output has different structure", func(t *testing.T) {
-		outputs := OutputMetadata{
-			outputName: map[string]interface{}{
-				"other": struct{}{},
-			},
-		}
-
-		gotValue, ok := outputs.GetMetadata(outputName, metadataKey)
-		require.False(t, ok, "GetMetadata should report that it did not find the value")
-		assert.Empty(t, gotValue, "GetMetadata should return an empty value when one isn't found")
-	})
-
 }
 
 func TestResultOutputs_SetContentDigest(t *testing.T) {
@@ -265,3 +244,19 @@ func TestResult_HasLogs(t *testing.T) {
 	r.OutputMetadata.SetGeneratedByBundle(OutputInvocationImageLogs, true)
 	assert.True(t, r.HasLogs(), "expected HasLogs to return true")
 }
+
+// Verify that when we unmarshal a result, the output metadata can be read back
+func TestResult_UnmarshalOutputMetadata(t *testing.T) {
+	data, err := ioutil.ReadFile("testdata/result.json")
+	require.NoError(t, err, "error reading testdata result")
+
+	var result Result
+	err = json.Unmarshal(data, &result)
+	require.NoError(t, err, "error unmarshaling result")
+
+	contentDigest, _ := result.OutputMetadata.GetContentDigest(OutputInvocationImageLogs)
+	assert.Equal(t, "sha256:28ccd0529aa1edefb0e771a28c31c0193f656718af985fed197235ba98fc5696", contentDigest, "the content digest output metadata could not be read")
+
+	generatedFlag, _ := result.OutputMetadata.GetGeneratedByBundle("output1")
+	assert.True(t, generatedFlag, "the generatedByBundle output metadata could not be read")
+}
diff --git a/claim/testdata/result.json b/claim/testdata/result.json
new file mode 100644
index 00000000..59fa2fb2
--- /dev/null
+++ b/claim/testdata/result.json
@@ -0,0 +1,16 @@
+{
+  "id": "01G1VJH2HP97B5B0N5S37KYMVG",
+  "claimId": "01G1VJGY43HT3KZN82DS6DDPWK",
+  "created": "2022-04-29T16:09:47.190534-05:00",
+  "status": "succeeded",
+  "outputs": {
+    "io.cnab.outputs.invocationImageLogs": {
+      "contentDigest": "sha256:28ccd0529aa1edefb0e771a28c31c0193f656718af985fed197235ba98fc5696",
+      "generatedByBundle": "false"
+    },
+    "output1": {
+      "contentDigest": "sha256:abc123",
+      "generatedByBundle": "true"
+    }
+  }
+}