diff --git a/apps/mobile/src/features/identity/IdentityAvatar.tsx b/apps/mobile/src/features/identity/IdentityAvatar.tsx
index 3e3ab28d65d..d640c03a80f 100644
--- a/apps/mobile/src/features/identity/IdentityAvatar.tsx
+++ b/apps/mobile/src/features/identity/IdentityAvatar.tsx
@@ -13,6 +13,7 @@ export function IdentityAvatar(props: {
   readonly name?: string | null | undefined;
   readonly size?: "micro" | "sm" | "md";
   readonly className?: string;
+  readonly highlighted?: boolean;
 }) {
   const model = identityAvatar({
     personId: props.personId,
@@ -26,10 +27,18 @@ export function IdentityAvatar(props: {
   return (
     <View
       accessibilityLabel={model.label}
-      className={cn("shrink-0 items-center justify-center rounded-full", box, props.className)}
-      style={{ backgroundColor: model.backgroundColor }}
+      className={cn(
+        "shrink-0 items-center justify-center rounded-full",
+        box,
+        props.highlighted && "bg-primary",
+        props.className,
+      )}
+      style={props.highlighted ? undefined : { backgroundColor: model.backgroundColor }}
     >
-      <Text className={cn("font-t3-bold", text)} style={{ color: model.color }}>
+      <Text
+        className={cn("font-t3-bold", text, props.highlighted && "text-primary-foreground")}
+        style={props.highlighted ? undefined : { color: model.color }}
+      >
         {model.initials}
       </Text>
     </View>
diff --git a/apps/mobile/src/features/identity/ParticipantStack.tsx b/apps/mobile/src/features/identity/ParticipantStack.tsx
index eda60df41f6..b53956727cb 100644
--- a/apps/mobile/src/features/identity/ParticipantStack.tsx
+++ b/apps/mobile/src/features/identity/ParticipantStack.tsx
@@ -53,28 +53,29 @@ export function ParticipantStack(props: {
         username={lead.username}
         name={lead.name}
         size="micro"
+        highlighted={lead.personId === claimPersonId}
       />
       {extras.length > 0 ? (
         <View
-          accessibilityElementsHidden
-          importantForAccessibility="no-hide-descendants"
-          className="size-3.5 items-center justify-center rounded-full bg-subtle"
+          accessibilityElementsHidden={!youParticipated}
+          importantForAccessibility={youParticipated ? "auto" : "no-hide-descendants"}
+          accessibilityLabel={youParticipated ? "You participated" : undefined}
+          className={cn(
+            "size-3.5 items-center justify-center rounded-full",
+            youParticipated ? "border border-primary bg-primary/15" : "bg-subtle",
+          )}
+          testID={youParticipated ? "you-participated-indicator" : undefined}
         >
-          <Text className="text-[8px] font-t3-medium text-foreground-tertiary">
+          <Text
+            className={cn(
+              "text-[8px] font-t3-medium",
+              youParticipated ? "text-primary" : "text-foreground-tertiary",
+            )}
+          >
             +{extras.length}
           </Text>
         </View>
       ) : null}
-      {youParticipated ? (
-        <View
-          accessibilityElementsHidden
-          importantForAccessibility="no-hide-descendants"
-          className="size-3.5 items-center justify-center rounded-full border border-primary bg-primary/15"
-          testID="you-participated-indicator"
-        >
-          <Text className="text-[9px] font-t3-bold text-primary">✓</Text>
-        </View>
-      ) : null}
     </View>
   );
 }
diff --git a/apps/mobile/src/features/identity/participantStackSurface.test.ts b/apps/mobile/src/features/identity/participantStackSurface.test.ts
index ef64d87a877..4cdcb3cab7b 100644
--- a/apps/mobile/src/features/identity/participantStackSurface.test.ts
+++ b/apps/mobile/src/features/identity/participantStackSurface.test.ts
@@ -13,7 +13,13 @@ describe("mobile participation indicator surface", () => {
     const listV2 = readSource("../threads/thread-list-v2-items.tsx");
     const board = readSource("../board/BoardScreen.tsx");
 
-    expect(stack).toContain('testID="you-participated-indicator"');
+    expect(stack).toContain('testID={youParticipated ? "you-participated-indicator"');
+    expect(stack).toContain("+{extras.length}");
+    expect(stack).toContain('"border border-primary bg-primary/15"');
+    expect(stack).not.toContain(">✓</Text>");
+    expect(stack).toContain("highlighted={lead.personId === claimPersonId}");
+    const avatar = readSource("./IdentityAvatar.tsx");
+    expect(avatar).toContain('props.highlighted && "bg-primary"');
     expect(stack).toContain("isClaimedNonStarterParticipant");
     expect(stack).toContain("You participated");
     expect(listV1).toContain("environmentId={thread.environmentId}");
diff --git a/apps/web/src/components/identity/IdentityAvatar.tsx b/apps/web/src/components/identity/IdentityAvatar.tsx
index d41462c5b9b..cee49d7b440 100644
--- a/apps/web/src/components/identity/IdentityAvatar.tsx
+++ b/apps/web/src/components/identity/IdentityAvatar.tsx
@@ -7,6 +7,7 @@ export function IdentityAvatar(props: {
   readonly name?: string | null | undefined;
   readonly size?: "micro" | "sm" | "md";
   readonly className?: string;
+  readonly highlighted?: boolean;
   /** `null` suppresses the native title when a parent owns richer tooltip content. */
   readonly title?: string | null;
 }) {
@@ -33,7 +34,10 @@ export function IdentityAvatar(props: {
         sizeClass,
         props.className,
       )}
-      style={{ backgroundColor: model.backgroundColor, color: model.color }}
+      style={{
+        backgroundColor: props.highlighted ? "var(--primary)" : model.backgroundColor,
+        color: props.highlighted ? "var(--primary-foreground)" : model.color,
+      }}
     >
       {model.initials}
     </span>
diff --git a/apps/web/src/components/identity/ParticipantStack.tsx b/apps/web/src/components/identity/ParticipantStack.tsx
index 760fa81b147..979e6a2d4c1 100644
--- a/apps/web/src/components/identity/ParticipantStack.tsx
+++ b/apps/web/src/components/identity/ParticipantStack.tsx
@@ -4,7 +4,6 @@ import {
   isClaimedNonStarterParticipant,
 } from "@t3tools/client-runtime/state/identity";
 import type { ThreadParticipantSummary } from "@t3tools/contracts";
-import { CheckIcon } from "lucide-react";
 import { identityClaimPersonIdByEnvironmentAtom } from "../../state/identity";
 import { IdentityAvatar } from "./IdentityAvatar";
 import { participantDisplayLabel } from "./ParticipantStack.logic";
@@ -53,24 +52,23 @@ export function ParticipantStack(props: {
         name={lead.name}
         size="micro"
         title={null}
+        highlighted={lead.personId === claimPersonId}
       />
       {extras.length > 0 ? (
         <span
-          className="inline-flex size-3.5 items-center justify-center rounded-full bg-muted text-[8px] font-medium text-muted-foreground"
-          aria-hidden
+          className={cn(
+            "inline-flex size-3.5 items-center justify-center rounded-full text-[8px] font-medium",
+            youParticipated
+              ? "bg-primary/15 text-primary ring-1 ring-primary/35"
+              : "bg-muted text-muted-foreground",
+          )}
+          aria-hidden={!youParticipated}
+          aria-label={youParticipated ? "You participated" : undefined}
+          data-testid={youParticipated ? "you-participated-indicator" : undefined}
         >
           +{extras.length}
         </span>
       ) : null}
-      {youParticipated ? (
-        <span
-          className="inline-flex size-3.5 items-center justify-center rounded-full bg-primary/15 text-primary ring-1 ring-primary/35"
-          aria-label="You participated"
-          data-testid="you-participated-indicator"
-        >
-          <CheckIcon className="size-2.5" aria-hidden />
-        </span>
-      ) : null}
     </span>
   );
 
@@ -91,6 +89,7 @@ export function ParticipantStack(props: {
               name={person.name}
               size="micro"
               title={null}
+              highlighted={person.personId === claimPersonId}
             />
             <span className="truncate text-foreground">
               {participantDisplayLabel(person)}
diff --git a/apps/web/src/forkSurfaceExistence.test.ts b/apps/web/src/forkSurfaceExistence.test.ts
index 22dbe806de8..7eb0383d37c 100644
--- a/apps/web/src/forkSurfaceExistence.test.ts
+++ b/apps/web/src/forkSurfaceExistence.test.ts
@@ -137,7 +137,13 @@ describe("fork surface existence (anti stack-drop)", () => {
     expect(stack).toContain("<TooltipPopup");
     expect(stack).toContain("participantDisplayLabel");
     expect(stack).toContain("title={null}");
-    expect(stack).toContain('data-testid="you-participated-indicator"');
+    expect(stack).toContain('data-testid={youParticipated ? "you-participated-indicator"');
+    expect(stack).toContain("+{extras.length}");
+    expect(stack).toContain('"bg-primary/15 text-primary ring-1 ring-primary/35"');
+    expect(stack).not.toContain("<CheckIcon");
+    expect(stack).toContain("highlighted={lead.personId === claimPersonId}");
+    const avatar = readSrc("components/identity/IdentityAvatar.tsx");
+    expect(avatar).toContain('props.highlighted ? "var(--primary)"');
     expect(stack).toContain("isClaimedNonStarterParticipant");
     expect(stack).toContain("· You");
     const stackLogic = readSrc("components/identity/ParticipantStack.logic.ts");