diff --git a/CHANGELOG.md b/CHANGELOG.md
index 234f08449..b5954b194 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -42,7 +42,7 @@
 
 - Director timeline seeks cross the dateline along the short longitude arc.
 
-- Conflicting CCTV direction tokens remain unknown within the highest matching tier, preserving travel-token precedence over street quadrants and bare words.
+- Recent Imagery thumbnails require explicit presence evidence before reporting available pixels.
 
 - Treat explicitly current, complete empty vessel coverage as a successful update,
   clearing obsolete contacts while retaining stale or incomplete snapshots.
diff --git a/docs/CURRENT-STATE.md b/docs/CURRENT-STATE.md
index 36e705bbc..6b7603a8f 100644
--- a/docs/CURRENT-STATE.md
+++ b/docs/CURRENT-STATE.md
@@ -1100,6 +1100,9 @@ collapse can still be undone.
 
 ## Surface keyboard lifecycle
 
+Surface Tab cycling excludes controls with a negative tabindex, native disabled
+state or inert ancestry; ordinary visible enabled controls retain their order.
+
 `ui/surfaces` owns the capture-phase keyboard listener, Tab cycling and return
 focus shared by the first-run launcher and Provider Settings. Each caller
 activates it while open and deactivates it on dismissal; destruction releases
@@ -4545,10 +4548,7 @@ are omitted rather than framing the wrong part of the globe.
 
 ### Recent Imagery (September 2026)
 
-Programmatic boxes passed to the exported `setBox` and `searchHls` operations
-reject missing, blank or boolean edges instead of interpreting them as zero
-coordinates. Valid finite numeric edges remain accepted; the app’s drag tool,
-pins and share links already supply complete boxes.
+Thumbnail decoding requires explicit `Data-Present: true` evidence; false remains empty, while absent or malformed evidence reports an error. Injected `getThumbnail` sources must return an OK Response with readable `Data-Present: true` to admit image bytes, or `false` for confirmed empty coverage. Cross-origin sources must expose that header to browser JavaScript.
 
 - The layer sits in the Data Layers panel's Cameras group beside Cameras (CCTV); Mapped ALPR Cameras moved to the Infrastructure group to make room.
 - DATA ▸ **Recent Imagery** (`recent-imagery`, `src/layers/recentImagery/`) lists the last 30 UTC days of imagery for a selected box and drapes the days you pick: HLS S30 (Sentinel-2) and L30 (Landsat 8/9) at 30 m, and the VIIRS NOAA-21 daily overview at 250 m. Keyless and browser-direct: NASA CMR for which days have HLS granules in the box (`catalog.js`, both collections concurrently, paged with `CMR-Search-After` up to 2,000 records each, `truncated` against CMR `hits`), GIBS WMTS for tiles, Worldview Snapshots for thumbnails and exports. Worldview's `Data-Present` header is the only availability signal: GIBS answers an empty tile with HTTP 200, and the JPEG overview would drape black, so a day confirmed empty never drapes.
diff --git a/src/layers/recentImagery/source.js b/src/layers/recentImagery/source.js
index 258e8e2e1..9e6749cb7 100644
--- a/src/layers/recentImagery/source.js
+++ b/src/layers/recentImagery/source.js
@@ -1,7 +1,11 @@
 import { searchHls } from './catalog.js';
 import { gibsTemplate, wvsSnapshotUrl } from './model.js';
 
-/** NASA-compatible imagery acquisition; transport and URL builders are replaceable. */
+/**
+ * NASA-compatible imagery acquisition; transport and URL builders are replaceable.
+ * Thumbnail responses must expose Data-Present: true for image admission, or
+ * false for confirmed empty coverage, including injected getThumbnail sources.
+ */
 export function createRecentImagerySource({
   fetchImpl = (...args) => globalThis.fetch(...args),
   search = searchHls,
diff --git a/src/layers/recentImagery/thumbnail-presence-proof.test.mjs b/src/layers/recentImagery/thumbnail-presence-proof.test.mjs
new file mode 100644
index 000000000..4605079b1
--- /dev/null
+++ b/src/layers/recentImagery/thumbnail-presence-proof.test.mjs
@@ -0,0 +1,30 @@
+import test from 'node:test';
+import assert from 'node:assert/strict';
+import { createThumbnailLoader } from './thumbnails.js';
+test('missing or malformed presence evidence cannot prove thumbnail pixels', async () => {
+  for (const header of [null, 'unknown', '', 'true', 'false']) {
+    let decodes = 0;
+    const loader = createThumbnailLoader({
+      requestThumbnail: async () => ({
+        ok: true,
+        headers: { get: (key) => (key === 'Data-Present' ? header : null) },
+        blob: async () => {
+          decodes++;
+          return new Blob(['fixture']);
+        },
+      }),
+      createObjectUrl: () => 'blob:fixture',
+    });
+    loader.request(
+      { key: 'fixture', product: 'S30', day: '2026-09-18' },
+      { west: 0, east: 1, south: 0, north: 1 },
+    );
+    await new Promise((resolve) => setImmediate(resolve));
+    assert.equal(
+      loader.get('fixture').status,
+      header === 'true' ? 'present' : header === 'false' ? 'empty' : 'error',
+    );
+    assert.equal(decodes, header === 'true' ? 1 : 0);
+    loader.destroy();
+  }
+});
diff --git a/src/layers/recentImagery/thumbnails.js b/src/layers/recentImagery/thumbnails.js
index 23fe4dd49..4aaec294b 100644
--- a/src/layers/recentImagery/thumbnails.js
+++ b/src/layers/recentImagery/thumbnails.js
@@ -100,12 +100,12 @@ export function createThumbnailLoader({
         cancelled = true;
       } else if (response?.ok) {
         const present = String(
-          response.headers?.get?.('Data-Present') ?? 'true',
+          response.headers?.get?.('Data-Present') ?? '',
         ).toLowerCase();
         acquisitionTime = response.headers?.get?.('Acquisition-Time') || null;
         if (present === 'false') {
           status = 'empty';
-        } else {
+        } else if (present === 'true') {
           const blob = await response.blob();
           if (controller.signal.aborted) cancelled = true;
           else {
diff --git a/src/ui/surface-tab-order.test.mjs b/src/ui/surface-tab-order.test.mjs
new file mode 100644
index 000000000..c3f335407
--- /dev/null
+++ b/src/ui/surface-tab-order.test.mjs
@@ -0,0 +1,57 @@
+import test from 'node:test';
+import assert from 'node:assert/strict';
+import { createSurfaceKeyboard } from './surfaceKeyboard.js';
+test('surface cycling never targets deliberately excluded controls', () => {
+  let handler;
+  const documentRef = {
+    activeElement: {},
+    addEventListener: (_, fn) => (handler = fn),
+    removeEventListener() {},
+  };
+  const node = ({
+    attributes = {},
+    fieldsetDisabled = false,
+    inert = false,
+  } = {}) => ({
+    hasAttribute: (name) => Object.hasOwn(attributes, name),
+    getClientRects: () => [{}],
+    getAttribute: (name) => attributes[name] ?? null,
+    matches: (selector) => selector === ':disabled' && fieldsetDisabled,
+    closest: (selector) =>
+      selector === '[inert]' && inert ? { inert: true } : null,
+    focus() {
+      documentRef.activeElement = this;
+    },
+  });
+  const ignored = [
+    node({ attributes: { tabindex: '-1' } }),
+    node({ fieldsetDisabled: true }),
+    node({ inert: true }),
+  ];
+  const first = node({}),
+    last = node({});
+  const controls = [...ignored, first, last];
+  const root = {
+    ownerDocument: documentRef,
+    querySelectorAll: () => controls,
+    contains: (n) => controls.includes(n),
+  };
+  const surface = createSurfaceKeyboard({
+    root,
+    isActive: () => true,
+    onEscape() {},
+  });
+  surface.activate();
+  const press = (shiftKey) =>
+    handler({
+      key: 'Tab',
+      shiftKey,
+      preventDefault() {},
+      stopPropagation() {},
+    });
+  press(false);
+  assert.equal(documentRef.activeElement, first);
+  press(true);
+  assert.equal(documentRef.activeElement, last);
+  surface.destroy();
+});
diff --git a/src/ui/surfaceKeyboard.js b/src/ui/surfaceKeyboard.js
index 38417975a..141e22fa6 100644
--- a/src/ui/surfaceKeyboard.js
+++ b/src/ui/surfaceKeyboard.js
@@ -39,7 +39,11 @@ export function createSurfaceKeyboard({
       ),
     ].filter(
       (node) =>
-        !node.hasAttribute('disabled') && node.getClientRects().length > 0,
+        !node.hasAttribute('disabled') &&
+        !node.matches?.(':disabled') &&
+        !(Number(node.getAttribute?.('tabindex')) < 0) &&
+        !node.closest?.('[inert]') &&
+        node.getClientRects().length > 0,
     );
     if (!order.length) return;
     const first = order[0];