diff --git a/src/app/c/[token]/d/[id]/__tests__/route.test.ts b/src/app/c/[token]/d/[id]/__tests__/route.test.ts
new file mode 100644
index 000000000..96072c5c7
--- /dev/null
+++ b/src/app/c/[token]/d/[id]/__tests__/route.test.ts
@@ -0,0 +1,308 @@
+import { describe, it, expect, vi, beforeEach } from "vitest";
+import { Buffer } from "node:buffer";
+import { NextRequest } from "next/server";
+
+/**
+ * v1.28 (document vault, Phase 3) — public share-scoped document serve route
+ * `GET /c/[token]/d/[id]`.
+ *
+ * Load-bearing behaviour under test: it resolves ONLY via the share token
+ * (never a session), confines serving to the link's frozen document set (a
+ * foreign / unknown / soft-deleted id → flat 404), re-enforces the passphrase
+ * gate and revocation/expiry BEFORE any decrypt, applies the identical
+ * serving-class posture as the owner route (inline Class A / attachment Class
+ * B + octet-stream + nosniff + no-store, no route-level CSP), strips EXIF from
+ * raster images on egress, and fails closed on a decrypt error.
+ */
+
+// Reversible crypto stub (mirrors the owner /original route test) so the
+// document codec round-trips without real keys.
+const decryptMock = vi.fn((s: string) =>
+  Buffer.from(s.replace(/^v1\./, ""), "base64").toString("utf8"),
+);
+vi.mock("@/lib/crypto", () => ({
+  encrypt: (s: string) => `v1.${Buffer.from(s, "utf8").toString("base64")}`,
+  decrypt: (s: string) => decryptMock(s),
+}));
+
+vi.mock("@/lib/db", () => ({
+  prisma: {
+    clinicianShareLinkDocument: { findUnique: vi.fn() },
+  },
+}));
+
+vi.mock("@/lib/clinician-share/resolve-share-token", () => ({
+  resolveShareGateState: vi.fn(),
+  resolveShareToken: vi.fn(),
+}));
+
+vi.mock("@/lib/clinician-share/unlock-cookie", () => ({
+  unlockCookieName: (h: string) => `hls_unlock_${h.slice(0, 16)}`,
+  verifyUnlockValue: vi.fn(() => true),
+}));
+
+vi.mock("@/lib/rate-limit", () => ({
+  checkRateLimit: vi
+    .fn()
+    .mockResolvedValue({ allowed: true, remaining: 299, resetAt: Date.now() }),
+  rateLimitHeaders: () => ({}),
+}));
+
+vi.mock("@/lib/logging/transports", () => ({ emitIfSampled: vi.fn() }));
+vi.mock("@/lib/db-compat", () => ({
+  ensureDbCompatibility: vi.fn().mockResolvedValue(undefined),
+}));
+vi.mock("next/headers", () => ({
+  headers: vi.fn(async () => ({ get: () => null })),
+  cookies: vi.fn(async () => ({
+    get: () => undefined,
+    set: () => {},
+    delete: () => {},
+  })),
+}));
+
+import { GET } from "../route";
+import { prisma } from "@/lib/db";
+import {
+  resolveShareGateState,
+  resolveShareToken,
+} from "@/lib/clinician-share/resolve-share-token";
+import { verifyUnlockValue } from "@/lib/clinician-share/unlock-cookie";
+import { checkRateLimit } from "@/lib/rate-limit";
+import { encryptDocumentToBytes } from "@/lib/documents/store";
+
+const TOKEN = "hls_000000000000000000000000000000000000000000000000";
+const OWNER = "owner-1";
+const SHARE_LINK_ID = "link-1";
+
+type Ctx = { params: Promise<{ token: string; id: string }> };
+const callGet = GET as unknown as (
+  req: NextRequest,
+  ctx: Ctx,
+) => Promise<Response>;
+
+function makeReq(id: string): NextRequest {
+  return new NextRequest(new URL(`http://localhost/c/${TOKEN}/d/${id}`));
+}
+function ctx(id: string): Ctx {
+  return { params: Promise.resolve({ token: TOKEN, id }) };
+}
+
+/** Seed a membership row whose document decrypts to `bytes` of `mimeType`. */
+function seedMembership(opts: {
+  id?: string;
+  userId?: string;
+  filename?: string | null;
+  mimeType: string;
+  bytes: Buffer;
+  deletedAt?: Date | null;
+}) {
+  vi.mocked(prisma.clinicianShareLinkDocument.findUnique).mockResolvedValue({
+    document: {
+      id: opts.id ?? "doc-1",
+      userId: opts.userId ?? OWNER,
+      filename: opts.filename ?? "report.pdf",
+      mimeType: opts.mimeType,
+      contentCodec: "base64v1",
+      contentEncrypted: encryptDocumentToBytes(opts.bytes),
+      deletedAt: opts.deletedAt ?? null,
+    },
+  } as never);
+}
+
+const PDF_BYTES = Buffer.from("%PDF-1.7 fake report body");
+
+// A minimal JPEG carrying a GPS marker inside an APP1 (Exif) segment.
+function jpegWithGps(): Buffer {
+  const payload = Buffer.concat([
+    Buffer.from("Exif\0\0"),
+    Buffer.from("GPSLatitude=48.137"),
+  ]);
+  const app1 = Buffer.concat([
+    Buffer.from([0xff, 0xe1]),
+    (() => {
+      const b = Buffer.alloc(2);
+      b.writeUInt16BE(payload.length + 2);
+      return b;
+    })(),
+    payload,
+  ]);
+  const sos = Buffer.concat([
+    Buffer.from([0xff, 0xda]),
+    Buffer.from([0x00, 0x08]),
+    Buffer.from([0x01, 0x01, 0x00, 0x3f, 0x00, 0x00]),
+    Buffer.from([0xaa, 0xbb]),
+  ]);
+  return Buffer.concat([Buffer.from([0xff, 0xd8]), app1, sos]);
+}
+
+beforeEach(() => {
+  vi.clearAllMocks();
+  decryptMock.mockImplementation((s: string) =>
+    Buffer.from(s.replace(/^v1\./, ""), "base64").toString("utf8"),
+  );
+  vi.mocked(verifyUnlockValue).mockReturnValue(true);
+  vi.mocked(checkRateLimit).mockResolvedValue({
+    allowed: true,
+    remaining: 299,
+    resetAt: Date.now(),
+  } as never);
+  // Default: a live, unprotected link resolving to the owner scope.
+  vi.mocked(resolveShareGateState).mockResolvedValue({
+    tokenHash: "hash-1",
+    passphraseHash: null,
+  } as never);
+  vi.mocked(resolveShareToken).mockResolvedValue({
+    shareLinkId: SHARE_LINK_ID,
+    ownerUserId: OWNER,
+    label: "Clinic",
+    rangeStart: new Date(),
+    rangeEnd: null,
+    sectionsJson: {},
+    resourceTypes: [],
+    allowFhirApi: false,
+    expiresAt: new Date(Date.now() + 3_600_000),
+  } as never);
+});
+
+describe("GET /c/[token]/d/[id] — share document serve", () => {
+  it("serves a PDF inline through the token, confined to the frozen set", async () => {
+    seedMembership({ mimeType: "application/pdf", bytes: PDF_BYTES });
+
+    const res = await callGet(makeReq("doc-1"), ctx("doc-1"));
+
+    expect(res.status).toBe(200);
+    expect(res.headers.get("Content-Type")).toBe("application/pdf");
+    expect(res.headers.get("Content-Disposition")).toContain("inline");
+    expect(res.headers.get("X-Content-Type-Options")).toBe("nosniff");
+    expect(res.headers.get("Cache-Control")).toBe("private, no-store");
+    // The response CSP is proxy-owned; the route sets none.
+    expect(res.headers.get("Content-Security-Policy")).toBeNull();
+    const out = Buffer.from(await res.arrayBuffer());
+    expect(out.equals(PDF_BYTES)).toBe(true);
+
+    // The membership lookup ties the id to THIS link (token-confined scope).
+    const arg = vi.mocked(prisma.clinicianShareLinkDocument.findUnique).mock
+      .calls[0][0];
+    expect(arg!.where).toEqual({
+      shareLinkId_documentId: {
+        shareLinkId: SHARE_LINK_ID,
+        documentId: "doc-1",
+      },
+    });
+  });
+
+  it("strips EXIF/GPS from a shared JPEG on egress", async () => {
+    const jpeg = jpegWithGps();
+    seedMembership({ mimeType: "image/jpeg", bytes: jpeg, filename: "p.jpg" });
+
+    const res = await callGet(makeReq("doc-1"), ctx("doc-1"));
+    expect(res.status).toBe(200);
+    const out = Buffer.from(await res.arrayBuffer());
+    // The GPS marker is gone; the image is strictly smaller than the original.
+    expect(out.includes(Buffer.from("GPSLatitude"))).toBe(false);
+    expect(out.length).toBeLessThan(jpeg.length);
+    // Still an inline image.
+    expect(res.headers.get("Content-Type")).toBe("image/jpeg");
+    expect(res.headers.get("Content-Disposition")).toContain("inline");
+  });
+
+  it("serves a Class B document as an opaque attachment (never inline)", async () => {
+    seedMembership({
+      mimeType:
+        "application/vnd.openxmlformats-officedocument.wordprocessingml.document",
+      bytes: Buffer.from("docx payload"),
+      filename: "letter.docx",
+    });
+    const res = await callGet(makeReq("doc-1"), ctx("doc-1"));
+    expect(res.status).toBe(200);
+    expect(res.headers.get("Content-Type")).toBe("application/octet-stream");
+    const disposition = res.headers.get("Content-Disposition") ?? "";
+    expect(disposition.startsWith("attachment;")).toBe(true);
+    expect(disposition).toContain("letter.docx");
+    expect(res.headers.get("X-Content-Type-Options")).toBe("nosniff");
+  });
+
+  it("never serves a would-be HTML/SVG payload inline (byte-class denies it)", async () => {
+    // HTML/SVG can never be stored (upload deny-list); even if a row carried
+    // such a type, the serving class forces attachment + octet-stream so it
+    // can never script in-origin.
+    for (const mime of ["text/html", "image/svg+xml"]) {
+      seedMembership({ mimeType: mime, bytes: Buffer.from("<svg/>") });
+      const res = await callGet(makeReq("doc-1"), ctx("doc-1"));
+      expect(res.headers.get("Content-Type")).toBe("application/octet-stream");
+      expect(res.headers.get("Content-Disposition")).toContain("attachment");
+    }
+  });
+
+  it("404s a document id not on the link's frozen set", async () => {
+    vi.mocked(prisma.clinicianShareLinkDocument.findUnique).mockResolvedValue(
+      null as never,
+    );
+    const res = await callGet(makeReq("foreign"), ctx("foreign"));
+    expect(res.status).toBe(404);
+  });
+
+  it("404s a soft-deleted document even if the membership row survives", async () => {
+    seedMembership({
+      mimeType: "application/pdf",
+      bytes: PDF_BYTES,
+      deletedAt: new Date(),
+    });
+    const res = await callGet(makeReq("doc-1"), ctx("doc-1"));
+    expect(res.status).toBe(404);
+  });
+
+  it("404s when the document owner does not match the token owner", async () => {
+    seedMembership({
+      mimeType: "application/pdf",
+      bytes: PDF_BYTES,
+      userId: "someone-else",
+    });
+    const res = await callGet(makeReq("doc-1"), ctx("doc-1"));
+    expect(res.status).toBe(404);
+  });
+
+  it("serves NOTHING for a revoked/expired/unknown token (gate null) — no decrypt", async () => {
+    vi.mocked(resolveShareGateState).mockResolvedValue(null as never);
+    const res = await callGet(makeReq("doc-1"), ctx("doc-1"));
+    expect(res.status).toBe(404);
+    // Revocation is enforced BEFORE any decrypt or membership lookup.
+    expect(prisma.clinicianShareLinkDocument.findUnique).not.toHaveBeenCalled();
+    expect(resolveShareToken).not.toHaveBeenCalled();
+  });
+
+  it("serves NOTHING for a protected link without a valid unlock cookie", async () => {
+    vi.mocked(resolveShareGateState).mockResolvedValue({
+      tokenHash: "hash-1",
+      passphraseHash: "hash(pass)",
+    } as never);
+    vi.mocked(verifyUnlockValue).mockReturnValue(false);
+    const res = await callGet(makeReq("doc-1"), ctx("doc-1"));
+    expect(res.status).toBe(404);
+    // The passphrase gate stands in front of any decrypt.
+    expect(prisma.clinicianShareLinkDocument.findUnique).not.toHaveBeenCalled();
+  });
+
+  it("429s when the per-link serve rate limit trips", async () => {
+    vi.mocked(checkRateLimit).mockResolvedValue({
+      allowed: false,
+      remaining: 0,
+      resetAt: Date.now(),
+    } as never);
+    const res = await callGet(makeReq("doc-1"), ctx("doc-1"));
+    expect(res.status).toBe(429);
+    expect(prisma.clinicianShareLinkDocument.findUnique).not.toHaveBeenCalled();
+  });
+
+  it("fails closed (500) on a decrypt error — never serves ciphertext", async () => {
+    seedMembership({ mimeType: "application/pdf", bytes: PDF_BYTES });
+    decryptMock.mockImplementation(() => {
+      throw new Error("unknown key id");
+    });
+    const res = await callGet(makeReq("doc-1"), ctx("doc-1"));
+    expect(res.status).toBe(500);
+    const body = (await res.json()) as { error: string };
+    expect(body.error).toBeTruthy();
+  });
+});