diff --git a/backend/src/intake/priceSource.ts b/backend/src/intake/priceSource.ts
new file mode 100644
index 0000000..ff87238
--- /dev/null
+++ b/backend/src/intake/priceSource.ts
@@ -0,0 +1,34 @@
+/**
+ * Where an item's price came from, and when that changes.
+ *
+ * This is the protection that used to live in the schema. Items are priced on
+ * arrival — the model's suggestion, or the 80.00 default — so nothing stops a
+ * number nobody chose from reaching the storefront except the review queue
+ * showing that it was never chosen.
+ *
+ * Pure and separately tested because the failure is silent. An item that sells
+ * at a default price looks exactly like one that sells at a chosen price;
+ * 80.00 was picked precisely because it reads as a decision rather than as an
+ * obvious sentinel the way 0.00 would.
+ */
+export type PriceSource = 'default' | 'ai' | 'admin';
+
+/**
+ * Editing the number is the admin taking responsibility for it, and it is the
+ * only thing that can. Publishing without touching the field deliberately does
+ * NOT confirm it — that would turn "I did not look at this" into "I approved
+ * this", which is the exact misrecording the review queue exists to prevent.
+ */
+export function nextPriceSource(
+  current: PriceSource,
+  submittedCents: number,
+  storedCents: number
+): PriceSource {
+  if (current === 'admin') return 'admin';
+  return submittedCents === storedCents ? current : 'admin';
+}
+
+/** Anything a person did not choose, which the screen marks visibly. */
+export function isUnconfirmed(source: PriceSource): boolean {
+  return source !== 'admin';
+}
diff --git a/backend/tests/unit/priceSource.test.ts b/backend/tests/unit/priceSource.test.ts
new file mode 100644
index 0000000..d967d35
--- /dev/null
+++ b/backend/tests/unit/priceSource.test.ts
@@ -0,0 +1,32 @@
+import { nextPriceSource, isUnconfirmed } from '../../src/intake/priceSource';
+
+describe('nextPriceSource', () => {
+  // Touching the number is the admin taking responsibility for it. That is the
+  // only event that can confirm a price.
+  it('becomes admin when the number changes', () => {
+    expect(nextPriceSource('default', 9500, 8000)).toBe('admin');
+    expect(nextPriceSource('ai', 4000, 4500)).toBe('admin');
+  });
+
+  // Publishing without touching the field must NOT silently confirm it. That
+  // is the whole failure this screen exists to prevent: an item selling at a
+  // number nobody chose, with nothing recording that.
+  it('leaves an untouched price unconfirmed', () => {
+    expect(nextPriceSource('default', 8000, 8000)).toBe('default');
+    expect(nextPriceSource('ai', 4500, 4500)).toBe('ai');
+  });
+
+  // Already confirmed stays confirmed, including when re-submitted unchanged.
+  it('keeps admin once set', () => {
+    expect(nextPriceSource('admin', 9500, 9500)).toBe('admin');
+    expect(nextPriceSource('admin', 7000, 9500)).toBe('admin');
+  });
+});
+
+describe('isUnconfirmed', () => {
+  it('treats anything but admin as unconfirmed', () => {
+    expect(isUnconfirmed('default')).toBe(true);
+    expect(isUnconfirmed('ai')).toBe(true);
+    expect(isUnconfirmed('admin')).toBe(false);
+  });
+});