diff --git a/dd-trace-core/src/main/java/datadog/trace/core/DDSpanContext.java b/dd-trace-core/src/main/java/datadog/trace/core/DDSpanContext.java
index f01d250f8bc..f1b12ffe40d 100644
--- a/dd-trace-core/src/main/java/datadog/trace/core/DDSpanContext.java
+++ b/dd-trace-core/src/main/java/datadog/trace/core/DDSpanContext.java
@@ -49,7 +49,6 @@
 import java.util.TreeMap;
 import java.util.concurrent.ConcurrentHashMap;
 import java.util.concurrent.ThreadLocalRandom;
-import java.util.concurrent.atomic.AtomicReferenceFieldUpdater;
 import java.util.function.Function;
 import javax.annotation.Nonnull;
 import org.slf4j.Logger;
@@ -165,16 +164,10 @@ public class DDSpanContext implements AgentSpanContext, ProfilerContext {
   private volatile boolean topLevel;
 
   /**
-   * This span's own propagation tags, when they differ from the trace's. Only a non-root span that
-   * is the target of a write (e.g. {@code _dd.p.ts}) gets one. Access via {@link
-   * #ownPropagationTags()}.
+   * This span's own propagation tags, when it was constructed with some while its trace already had
+   * propagation tags. Otherwise null, and the trace's are used.
    */
-  private volatile PropagationTags propagationTags;
-
-  private static final AtomicReferenceFieldUpdater<DDSpanContext, PropagationTags>
-      PROPAGATION_TAGS =
-          AtomicReferenceFieldUpdater.newUpdater(
-              DDSpanContext.class, PropagationTags.class, "propagationTags");
+  private final PropagationTags propagationTags;
 
   private volatile PathwayContext pathwayContext;
 
@@ -367,10 +360,13 @@ public DDSpanContext(
 
     if (propagationTags != null) {
       propagationTags.updateTraceIdHighOrderBits(this.traceId.toHighOrderLong());
-      if (traceCollector.initPropagationTags(propagationTags) != propagationTags) {
-        // the trace already has propagation tags, so these are this span's own
-        this.propagationTags = propagationTags;
-      }
+      // if the trace already has propagation tags, these are this span's own
+      this.propagationTags =
+          traceCollector.initPropagationTags(propagationTags) != propagationTags
+              ? propagationTags
+              : null;
+    } else {
+      this.propagationTags = null;
     }
     if (origin != null) {
       setOrigin(origin);
@@ -389,19 +385,6 @@ private PropagationTags tracePropagationTags() {
     return tags != null ? tags : traceCollector.initPropagationTags(newEmptyPropagationTags());
   }
 
-  /**
-   * Returns this span's own propagation tags: the trace's for the local root, otherwise an instance
-   * created on first use.
-   */
-  private PropagationTags ownPropagationTags() {
-    PropagationTags tags = ownPropagationTagsIfPresent();
-    if (tags != null) {
-      return tags;
-    }
-    PropagationTags created = newEmptyPropagationTags();
-    return PROPAGATION_TAGS.compareAndSet(this, null, created) ? created : propagationTags;
-  }
-
   /** This span's own propagation tags, or null if a non-root span has none yet. */
   private PropagationTags ownPropagationTagsIfPresent() {
     PropagationTags tags = propagationTags;
@@ -659,11 +642,13 @@ public void forceKeep(byte samplingMechanism) {
   }
 
   public void addPropagatedTraceSource(final int value) {
-    ownPropagationTags().addTraceSource(value);
+    // trace level, so it's propagated whichever span it's set on
+    tracePropagationTags().addTraceSource(value);
   }
 
   public void updateDebugPropagation(String value) {
-    ownPropagationTags().updateDebugPropagation(value);
+    // trace level, so it's propagated whichever span it's set on
+    tracePropagationTags().updateDebugPropagation(value);
   }
 
   /**
diff --git a/dd-trace-core/src/test/java/datadog/trace/core/ChildSpanPropagationTagsTest.java b/dd-trace-core/src/test/java/datadog/trace/core/ChildSpanPropagationTagsTest.java
index 6d2b3339ffa..6c95a5c50f2 100644
--- a/dd-trace-core/src/test/java/datadog/trace/core/ChildSpanPropagationTagsTest.java
+++ b/dd-trace-core/src/test/java/datadog/trace/core/ChildSpanPropagationTagsTest.java
@@ -93,27 +93,37 @@ void rootSerializationUnaffectedByChildren() {
   }
 
   @Test
-  void traceSourceOnChildStaysOnChild() {
+  void traceSourceOnChildIsTraceLevel() {
     DDSpan root = (DDSpan) tracer.buildSpan("test", "root").start();
     DDSpan child = childOf(root);
 
     child.setTag("_dd.p.ts", ProductTraceSource.ASM);
 
-    assertTrue(child.spanContext().hasOwnPropagationTags());
-    assertEquals("02", ownTags(child).get("_dd.p.ts"));
-    assertFalse(root.spanContext().getPropagationTags().createTagMap().containsKey("_dd.p.ts"));
+    assertTraceLevel(root, child, "_dd.p.ts", "02");
   }
 
   @Test
-  void debugPropagationOnChildStaysOnChild() {
+  void debugPropagationOnChildIsTraceLevel() {
     DDSpan root = (DDSpan) tracer.buildSpan("test", "root").start();
     DDSpan child = childOf(root);
 
     child.setTag("_dd.p.debug", "probe");
 
-    assertTrue(child.spanContext().hasOwnPropagationTags());
-    assertEquals("probe", ownTags(child).get("_dd.p.debug"));
-    assertFalse(root.spanContext().getPropagationTags().createTagMap().containsKey("_dd.p.debug"));
+    assertTraceLevel(root, child, "_dd.p.debug", "probe");
+  }
+
+  /** A tag set on a child lands on the trace: injected, and serialized with the local root. */
+  private void assertTraceLevel(DDSpan root, DDSpan child, String tag, String value) {
+    assertFalse(child.spanContext().hasOwnPropagationTags());
+    PropagationTags trace = root.spanContext().getPropagationTags();
+    assertSame(trace, child.spanContext().getPropagationTags());
+    assertEquals(value, trace.createTagMap().get(tag));
+    assertTrue(
+        trace.headerValue(PropagationTags.HeaderType.DATADOG).contains(tag + "=" + value),
+        trace.headerValue(PropagationTags.HeaderType.DATADOG));
+    assertEquals(value, tags(root, ROOT_PROPAGATION_TAGS).get(tag));
+    assertEquals(value, ownTags(root).get(tag));
+    assertEquals(expectedOwnTags(child), ownTags(child));
   }
 
   private DDSpan extractedRoot(DDTraceId traceId, String header) {