diff --git a/src/__tests__/fixtures/mock-deps.ts b/src/__tests__/fixtures/mock-deps.ts
index 316622a9..4fd4c836 100644
--- a/src/__tests__/fixtures/mock-deps.ts
+++ b/src/__tests__/fixtures/mock-deps.ts
@@ -1,22 +1,31 @@
 import { jest } from "@jest/globals";
-import { Dependencies, OctokitClient, Logger } from "../../types/Dependencies.js";
+import {
+  Dependencies,
+  OctokitClient,
+  Logger,
+} from "../../types/Dependencies.js";
 
-
-export function createMockLogger(): Logger & { [K in keyof Logger]: jest.Mock } {
-    return {
-      info: jest.fn<any>(),
-      error: jest.fn<any>(),
-      warning: jest.fn<any>(),
-      debug: jest.fn<any>(),
-    };
-  }
+export function createMockLogger(): Logger & {
+  [K in keyof Logger]: jest.Mock;
+} {
+  return {
+    info: jest.fn<any>(),
+    error: jest.fn<any>(),
+    warning: jest.fn<any>(),
+    debug: jest.fn<any>(),
+  };
+}
 
 // creates a mock OctokitClient with sensible defaults
-export function createMockOctokit(overrides: Partial<DeepPartial<OctokitClient>> = {}): OctokitClient {
+export function createMockOctokit(
+  overrides: Partial<DeepPartial<OctokitClient>> = {},
+): OctokitClient {
   return {
     rest: {
       repos: {
-        get: overrides.rest?.repos?.get as OctokitClient["rest"]["repos"]["get"] ??
+        get:
+          (overrides.rest?.repos
+            ?.get as OctokitClient["rest"]["repos"]["get"]) ??
           jest.fn<any>().mockResolvedValue({
             data: {
               name: "test-repo",
@@ -28,23 +37,32 @@ export function createMockOctokit(overrides: Partial<DeepPartial<OctokitClient>>
               created_at: "2024-01-01T00:00:00Z",
               updated_at: "2024-06-01T00:00:00Z",
               default_branch: "main",
+              fork: false,
+              parent: null,
             },
           }),
-        listLanguages: overrides.rest?.repos?.listLanguages as OctokitClient["rest"]["repos"]["listLanguages"] ??
+        listLanguages:
+          (overrides.rest?.repos
+            ?.listLanguages as OctokitClient["rest"]["repos"]["listLanguages"]) ??
           jest.fn<any>().mockResolvedValue({
             data: { TypeScript: 5000, JavaScript: 2000 },
           }),
-        getContent: overrides.rest?.repos?.getContent as OctokitClient["rest"]["repos"]["getContent"] ??
+        getContent:
+          (overrides.rest?.repos
+            ?.getContent as OctokitClient["rest"]["repos"]["getContent"]) ??
           jest.fn<any>().mockResolvedValue({
             data: { sha: "abc123" },
           }),
-        createOrUpdateFileContents: overrides.rest?.repos?.createOrUpdateFileContents as OctokitClient["rest"]["repos"]["createOrUpdateFileContents"] ??
+        createOrUpdateFileContents:
+          (overrides.rest?.repos
+            ?.createOrUpdateFileContents as OctokitClient["rest"]["repos"]["createOrUpdateFileContents"]) ??
           jest.fn<any>().mockResolvedValue({
             data: { commit: { sha: "def456" } },
           }),
       },
     },
-    createPullRequest: overrides.createPullRequest as OctokitClient["createPullRequest"] ??
+    createPullRequest:
+      (overrides.createPullRequest as OctokitClient["createPullRequest"]) ??
       jest.fn<any>().mockResolvedValue({
         data: { html_url: "https://github.com/test-owner/test-repo/pull/1" },
       }),
@@ -52,7 +70,9 @@ export function createMockOctokit(overrides: Partial<DeepPartial<OctokitClient>>
 }
 
 // creates a full mock Dependencies object with sensible defaults
-export function createMockDeps(overrides: Partial<Dependencies> = {}): Dependencies {
+export function createMockDeps(
+  overrides: Partial<Dependencies> = {},
+): Dependencies {
   const mockOctokit = createMockOctokit();
 
   return {
@@ -84,4 +104,4 @@ export function createMockDeps(overrides: Partial<Dependencies> = {}): Dependenc
 // helper type for deep partial overrides
 type DeepPartial<T> = {
   [P in keyof T]?: T[P] extends object ? DeepPartial<T[P]> : T[P];
-};
\ No newline at end of file
+};
diff --git a/src/__tests__/unit/helper.test.ts b/src/__tests__/unit/helper.test.ts
index 04af7bbe..74d05ae6 100644
--- a/src/__tests__/unit/helper.test.ts
+++ b/src/__tests__/unit/helper.test.ts
@@ -37,7 +37,9 @@ describe("createHelpers - calculateMetaData", () => {
 
     expect(result.name).toBe("test-repo");
     expect(result.description).toBe("A test repository");
-    expect(result.repositoryURL).toBe("https://github.com/test-owner/test-repo");
+    expect(result.repositoryURL).toBe(
+      "https://github.com/test-owner/test-repo",
+    );
     expect(result.repositoryVisibility).toBe("public");
     expect(result.languages).toEqual(["TypeScript", "JavaScript"]);
     expect(result.laborHours).toBeGreaterThan(0);
@@ -193,7 +195,9 @@ describe("createHelpers - pushDirectlyWithFallback", () => {
 
     await helpers.pushDirectlyWithFallback({ name: "test" } as any, "main");
 
-    expect(adminOctokit.rest.repos.createOrUpdateFileContents).toHaveBeenCalled();
+    expect(
+      adminOctokit.rest.repos.createOrUpdateFileContents,
+    ).toHaveBeenCalled();
     expect(deps.setOutput).toHaveBeenCalledWith("method_used", "direct_push");
   });
 });
@@ -215,7 +219,11 @@ describe("createHelpers - validateOnly", () => {
   it("succeeds for valid code.json", async () => {
     const validCodeJSON = await import("../fixtures/test-code.json");
     const deps = createMockDeps({
-      readFile: jest.fn<any>().mockResolvedValue(JSON.stringify(validCodeJSON.default ?? validCodeJSON)),
+      readFile: jest
+        .fn<any>()
+        .mockResolvedValue(
+          JSON.stringify(validCodeJSON.default ?? validCodeJSON),
+        ),
     });
     const helpers = createHelpers(deps);
 
@@ -383,6 +391,60 @@ describe("createHelpers - detectReusedCode", () => {
   });
 });
 
+describe("createHelpers - detectForkParent", () => {
+  function mockRepoGet(data: Record<string, unknown>): Dependencies {
+    return createMockDeps({
+      octokit: createMockOctokit({
+        rest: {
+          repos: {
+            get: jest.fn<any>().mockResolvedValue({ data }),
+          },
+        },
+      }),
+    });
+  }
+
+  it("returns the upstream parent when the repo is a fork", async () => {
+    const deps = mockRepoGet({
+      fork: true,
+      parent: {
+        full_name: "upstream-owner/upstream-repo",
+        html_url: "https://github.com/upstream-owner/upstream-repo",
+      },
+    });
+
+    expect(await createHelpers(deps).detectForkParent()).toEqual({
+      name: "upstream-owner/upstream-repo",
+      URL: "https://github.com/upstream-owner/upstream-repo",
+    });
+  });
+
+  it("returns null when the repo is not a fork", async () => {
+    const deps = mockRepoGet({ fork: false, parent: null });
+    expect(await createHelpers(deps).detectForkParent()).toBeNull();
+  });
+
+  it("returns null when fork is true but parent is missing", async () => {
+    const deps = mockRepoGet({ fork: true });
+    expect(await createHelpers(deps).detectForkParent()).toBeNull();
+  });
+
+  it("returns null and logs when the API call fails", async () => {
+    const deps = createMockDeps({
+      octokit: createMockOctokit({
+        rest: {
+          repos: {
+            get: jest.fn<any>().mockRejectedValue(new Error("API down")),
+          },
+        },
+      }),
+    });
+
+    expect(await createHelpers(deps).detectForkParent()).toBeNull();
+    expect(deps.log.error).toHaveBeenCalled();
+  });
+});
+
 describe("mergeReusedCode", () => {
   it("appends detected entries to existing ones", () => {
     const existing = [{ name: "Other Gov Tool", URL: "https://example.gov" }];
@@ -417,4 +479,4 @@ describe("GOV_DEPENDENCIES integrity", () => {
     expect(entry.name.trim()).not.toBe("");
     expect(entry.URL).toMatch(/^https:\/\//);
   });
-});
\ No newline at end of file
+});
diff --git a/src/__tests__/unit/main.test.ts b/src/__tests__/unit/main.test.ts
index 39a5b186..475666be 100644
--- a/src/__tests__/unit/main.test.ts
+++ b/src/__tests__/unit/main.test.ts
@@ -1,12 +1,23 @@
-import { describe, it, expect, jest, beforeEach, afterEach } from "@jest/globals";
+import {
+  describe,
+  it,
+  expect,
+  jest,
+  beforeEach,
+  afterEach,
+} from "@jest/globals";
 import { runWithDeps, filterValidFields, getMetaData } from "../../main.js";
 import { createHelpers } from "../../helper.js";
-import { createMockDeps } from "../fixtures/mock-deps.js";
+import { createMockDeps, createMockOctokit } from "../fixtures/mock-deps.js";
 import validCodeJSON from "../fixtures/test-code.json";
 
 describe("filterValidFields", () => {
   it("keeps known fields", () => {
-    const result = filterValidFields({ name: "test", version: "1.0", description: "hi" });
+    const result = filterValidFields({
+      name: "test",
+      version: "1.0",
+      description: "hi",
+    });
     expect(result).toHaveProperty("name", "test");
     expect(result).toHaveProperty("version", "1.0");
   });
@@ -23,10 +34,15 @@ describe("getMetaData", () => {
     const deps = createMockDeps();
     const helpers = createHelpers(deps);
 
-    const existing = { ...validCodeJSON, feedbackMechanism: "https://custom.example.com/feedback" } as any;
+    const existing = {
+      ...validCodeJSON,
+      feedbackMechanism: "https://custom.example.com/feedback",
+    } as any;
     const result = await getMetaData(helpers, deps, existing);
 
-    expect(result.feedbackMechanism).toBe("https://custom.example.com/feedback");
+    expect(result.feedbackMechanism).toBe(
+      "https://custom.example.com/feedback",
+    );
   });
 
   it("defaults feedbackMechanism to issues URL", async () => {
@@ -57,6 +73,42 @@ describe("getMetaData", () => {
 
     expect(result.contractNumber).toEqual(["LEGACY-001"]);
   });
+
+  it("adds the fork upstream to reusedCode", async () => {
+    const forkOctokit = createMockOctokit({
+      rest: {
+        repos: {
+          get: jest.fn<any>().mockResolvedValue({
+            data: {
+              name: "test-repo",
+              description: "A forked repository",
+              html_url: "https://github.com/test-owner/test-repo",
+              private: false,
+              forks_count: 0,
+              topics: [],
+              created_at: "2024-01-01T00:00:00Z",
+              updated_at: "2024-06-01T00:00:00Z",
+              default_branch: "main",
+              fork: true,
+              parent: {
+                full_name: "upstream-owner/upstream-repo",
+                html_url: "https://github.com/upstream-owner/upstream-repo",
+              },
+            },
+          }),
+        },
+      },
+    });
+    const deps = createMockDeps({ octokit: forkOctokit });
+    const helpers = createHelpers(deps);
+
+    const result = await getMetaData(helpers, deps, null);
+
+    expect(result.reusedCode).toContainEqual({
+      name: "upstream-owner/upstream-repo",
+      URL: "https://github.com/upstream-owner/upstream-repo",
+    });
+  });
 });
 
 describe("runWithDeps", () => {
@@ -106,9 +158,13 @@ describe("runWithDeps", () => {
     const adminOctokit = {
       rest: {
         repos: {
-          get: jest.fn<any>().mockResolvedValue({ data: { default_branch: "main" } }),
+          get: jest
+            .fn<any>()
+            .mockResolvedValue({ data: { default_branch: "main" } }),
           listLanguages: jest.fn<any>().mockResolvedValue({ data: {} }),
-          getContent: jest.fn<any>().mockResolvedValue({ data: { sha: "abc" } }),
+          getContent: jest
+            .fn<any>()
+            .mockResolvedValue({ data: { sha: "abc" } }),
           createOrUpdateFileContents: jest.fn<any>().mockResolvedValue({
             data: { commit: { sha: "pushed123" } },
           }),
@@ -125,7 +181,9 @@ describe("runWithDeps", () => {
 
     await runWithDeps(deps);
 
-    expect(adminOctokit.rest.repos.createOrUpdateFileContents).toHaveBeenCalled();
+    expect(
+      adminOctokit.rest.repos.createOrUpdateFileContents,
+    ).toHaveBeenCalled();
     expect(deps.setOutput).toHaveBeenCalledWith("method_used", "direct_push");
   });
 
@@ -158,4 +216,4 @@ describe("runWithDeps", () => {
       expect.stringContaining("Action failed"),
     );
   });
-});
\ No newline at end of file
+});
diff --git a/src/helper.ts b/src/helper.ts
index 521cf180..57be7b12 100644
--- a/src/helper.ts
+++ b/src/helper.ts
@@ -7,7 +7,8 @@ import { ReusedCodeEntry, lookupGovDependency } from "./gov-dependencies.js";
 const HOURS_PER_MONTH = 730.001;
 
 export function createHelpers(deps: Dependencies) {
-  const { owner, repo, octokit, adminOctokit, log, setOutput, isArchived } = deps;
+  const { owner, repo, octokit, adminOctokit, log, setOutput, isArchived } =
+    deps;
 
   //===============================================
   // Meta Data
@@ -78,7 +79,9 @@ export function createHelpers(deps: Dependencies) {
 
   async function getLaborHours(): Promise<number> {
     try {
-      const { stdout } = await deps.exec(`scc /github/workspace --format json2`);
+      const { stdout } = await deps.exec(
+        `scc /github/workspace --format json2`,
+      );
       const sccData = JSON.parse(stdout);
 
       const laborHours = Math.ceil(
@@ -124,6 +127,26 @@ export function createHelpers(deps: Dependencies) {
     }
   }
 
+  //===============================================
+  // Fork Upstream
+  //===============================================
+  async function detectForkParent(): Promise<ReusedCodeEntry | null> {
+    try {
+      const repoData = await octokit.rest.repos.get({ owner, repo });
+      const { fork, parent } = repoData.data;
+
+      if (!fork || !parent) return null;
+
+      return {
+        name: parent.full_name,
+        URL: parent.html_url,
+      };
+    } catch (error) {
+      log.error(`Failed to detect fork parent: ${error}`);
+      return null;
+    }
+  }
+
   async function getBaseBranch(): Promise<string> {
     if (deps.branch) {
       return deps.branch;
@@ -179,10 +202,7 @@ export function createHelpers(deps: Dependencies) {
     }
   }
 
-  async function sendPR(
-    updatedCodeJSON: CodeJSON,
-    baseBranchName: string,
-  ) {
+  async function sendPR(updatedCodeJSON: CodeJSON, baseBranchName: string) {
     try {
       const formattedContent = JSON.stringify(updatedCodeJSON, null, 2) + "\n";
       const headBranchName = `code-json-${new Date().getTime()}`;
@@ -190,7 +210,9 @@ export function createHelpers(deps: Dependencies) {
       const PR = await octokit.createPullRequest({
         owner,
         repo,
-        title: isArchived ? "Update code.json for archival" : "Update code.json",
+        title: isArchived
+          ? "Update code.json for archival"
+          : "Update code.json",
         body: isArchived ? bodyOfArchivalPR() : bodyOfPR(),
         base: baseBranchName,
         head: headBranchName,
@@ -258,7 +280,9 @@ export function createHelpers(deps: Dependencies) {
         sha: currentFileSha,
       });
 
-      log.info(`Successfully pushed commit with PAT: ${result.data.commit.sha}`);
+      log.info(
+        `Successfully pushed commit with PAT: ${result.data.commit.sha}`,
+      );
 
       setOutput("updated", true);
       setOutput("commit_sha", result.data.commit.sha);
@@ -302,6 +326,7 @@ export function createHelpers(deps: Dependencies) {
   return {
     calculateMetaData,
     detectReusedCode,
+    detectForkParent,
     mergeReusedCode,
     getBaseBranch,
     validateOnly,
diff --git a/src/main.ts b/src/main.ts
index 0c74d746..496e5729 100644
--- a/src/main.ts
+++ b/src/main.ts
@@ -69,7 +69,9 @@ const baselineCodeJSON: Partial<CodeJSON> = {
 
 export { baselineCodeJSON };
 
-function filterValidFields(existingCodeJSON: Record<string, unknown>): Partial<CodeJSON> {
+function filterValidFields(
+  existingCodeJSON: Record<string, unknown>,
+): Partial<CodeJSON> {
   const validKeys = new Set(Object.keys(baselineCodeJSON));
   const filtered: Record<string, unknown> = {};
 
@@ -136,10 +138,14 @@ async function getMetaData(
     tags?.push("archived");
   }
 
-  // detect government-made dependencies and merge with any existing reusedCode
+  // detect the fork upstream and government-made dependencies, then merge with any existing reusedCode
+  const [forkParent, detectedDeps] = await Promise.all([
+    helpers.detectForkParent(),
+    helpers.detectReusedCode(),
+  ]);
   const reusedCode = helpers.mergeReusedCode(
     existingCodeJSON?.reusedCode ?? [],
-    await helpers.detectReusedCode(),
+    [...(forkParent ? [forkParent] : []), ...detectedDeps],
   );
 
   return {
@@ -234,4 +240,4 @@ export async function runWithDeps(deps: Dependencies): Promise<void> {
 export async function run(): Promise<void> {
   const deps = createProductionDeps();
   return runWithDeps(deps);
-}
\ No newline at end of file
+}
diff --git a/src/types/Dependencies.ts b/src/types/Dependencies.ts
index c00f470d..c2c28d18 100644
--- a/src/types/Dependencies.ts
+++ b/src/types/Dependencies.ts
@@ -32,8 +32,16 @@ export interface OctokitClient {
   rest: {
     repos: {
       get: (params: { owner: string; repo: string }) => Promise<RepoResponse>;
-      listLanguages: (params: { owner: string; repo: string }) => Promise<LanguagesResponse>;
-      getContent: (params: { owner: string; repo: string; path: string; ref: string }) => Promise<ContentResponse>;
+      listLanguages: (params: {
+        owner: string;
+        repo: string;
+      }) => Promise<LanguagesResponse>;
+      getContent: (params: {
+        owner: string;
+        repo: string;
+        path: string;
+        ref: string;
+      }) => Promise<ContentResponse>;
       createOrUpdateFileContents: (params: {
         owner: string;
         repo: string;
@@ -71,6 +79,11 @@ export interface RepoResponse {
     created_at: string;
     updated_at: string;
     default_branch: string;
+    fork?: boolean;
+    parent?: {
+      full_name: string;
+      html_url: string;
+    } | null;
   };
 }
 
@@ -86,4 +99,4 @@ export interface CommitResponse {
   data: {
     commit: { sha: string };
   };
-}
\ No newline at end of file
+}