diff --git a/signalfx-codahale/src/main/java/com/signalfx/codahale/reporter/MetricMetadataImpl.java b/signalfx-codahale/src/main/java/com/signalfx/codahale/reporter/MetricMetadataImpl.java
index 631e3acc..07bd514b 100644
--- a/signalfx-codahale/src/main/java/com/signalfx/codahale/reporter/MetricMetadataImpl.java
+++ b/signalfx-codahale/src/main/java/com/signalfx/codahale/reporter/MetricMetadataImpl.java
@@ -14,7 +14,7 @@
 import com.signalfx.codahale.metrics.MetricBuilder;
 import com.signalfx.metrics.protobuf.SignalFxProtocolBuffers.MetricType;
 
-public class MetricMetadataImpl implements MetricMetadata {
+public final class MetricMetadataImpl implements MetricMetadata {
     private final ConcurrentMap<Metric, Metadata> metaDataCollection;
 
     public MetricMetadataImpl() {
diff --git a/signalfx-codahale/src/main/java/com/signalfx/codahale/reporter/SignalFxReporter.java b/signalfx-codahale/src/main/java/com/signalfx/codahale/reporter/SignalFxReporter.java
index 153fb7d9..4a5eb4f5 100644
--- a/signalfx-codahale/src/main/java/com/signalfx/codahale/reporter/SignalFxReporter.java
+++ b/signalfx-codahale/src/main/java/com/signalfx/codahale/reporter/SignalFxReporter.java
@@ -40,7 +40,7 @@
  * @deprecated Migrate to OpenTelemetry to send metric telemetry to Splunk.
  */
 @Deprecated
-public class SignalFxReporter extends ScheduledReporter {
+public final class SignalFxReporter extends ScheduledReporter {
     private final AggregateMetricSender aggregateMetricSender;
     private final Set<MetricDetails> detailsToAdd;
     private final MetricMetadata metricMetadata;
diff --git a/signalfx-yammer/src/main/java/com/signalfx/codahale/reporter/MetricMetadataImpl.java b/signalfx-yammer/src/main/java/com/signalfx/codahale/reporter/MetricMetadataImpl.java
index 48efbce8..5e6d926f 100644
--- a/signalfx-yammer/src/main/java/com/signalfx/codahale/reporter/MetricMetadataImpl.java
+++ b/signalfx-yammer/src/main/java/com/signalfx/codahale/reporter/MetricMetadataImpl.java
@@ -16,7 +16,7 @@
  *
  */
 
-public class MetricMetadataImpl implements MetricMetadata {
+public final class MetricMetadataImpl implements MetricMetadata {
     private final ConcurrentMap<Metric, Metadata> metaDataCollection;
 
     public MetricMetadataImpl() {
diff --git a/signalfx-yammer/src/main/java/com/signalfx/codahale/reporter/SignalFxReporter.java b/signalfx-yammer/src/main/java/com/signalfx/codahale/reporter/SignalFxReporter.java
index b2bc3924..e107ab63 100644
--- a/signalfx-yammer/src/main/java/com/signalfx/codahale/reporter/SignalFxReporter.java
+++ b/signalfx-yammer/src/main/java/com/signalfx/codahale/reporter/SignalFxReporter.java
@@ -37,7 +37,7 @@
  * @deprecated Migrate to OpenTelemetry to send metric telemetry to Splunk.
  */
 @Deprecated
-public class SignalFxReporter extends CustomScheduledReporter {
+public final class SignalFxReporter extends CustomScheduledReporter {
     private final AggregateMetricSender aggregateMetricSender;
     private final Set<MetricDetails> detailsToAdd;
     private final MetricMetadata metricMetadata;