diff --git a/packages/superagent-wrapper/src/request.ts b/packages/superagent-wrapper/src/request.ts
index 41d9dd5e..d4147412 100644
--- a/packages/superagent-wrapper/src/request.ts
+++ b/packages/superagent-wrapper/src/request.ts
@@ -138,8 +138,7 @@ const patchRequest = <
         });
       }
       return pipe(
-        // deep copy to prevent modification of the inputs by sketchy codecs
-        route.response[status].decode(structuredClone(res.body)),
+        route.response[status].decode(res.body),
         E.map((body) =>
           decodedResponse<Route>({
             status,
@@ -195,8 +194,7 @@ export const requestForRoute =
     route: Route,
   ): BoundRequestFactory<Req, Route> =>
   (params: h.RequestType<Route>): PatchedRequest<Req, Route> => {
-    // deep copy to prevent modification of the inputs by sketchy codecs
-    const reqProps = route.request.encode(structuredClone(params));
+    const reqProps = route.request.encode(params);
 
     let path = route.path;
     for (const key in reqProps.params) {
diff --git a/packages/superagent-wrapper/test/request.test.ts b/packages/superagent-wrapper/test/request.test.ts
index 9f64ab3f..eee3e5ef 100644
--- a/packages/superagent-wrapper/test/request.test.ts
+++ b/packages/superagent-wrapper/test/request.test.ts
@@ -45,37 +45,6 @@ const PostTestRoute = h.httpRoute({
   },
 });
 
-const PostOptionalTestRoute = h.httpRoute({
-  path: '/test/optional/{id}',
-  method: 'POST',
-  request: h.httpRequest({
-    query: {
-      foo: t.string,
-    },
-    params: {
-      id: NumberFromString,
-    },
-    body: {
-      bar: t.number,
-      optional: h.optionalized({
-        baz: t.boolean,
-        qux: h.optional(t.string),
-      }),
-    },
-  }),
-  response: {
-    200: t.type({
-      id: t.number,
-      foo: t.string,
-      bar: t.number,
-      baz: t.boolean,
-    }),
-    401: t.type({
-      message: t.string,
-    }),
-  },
-});
-
 const HeaderGetTestRoute = h.httpRoute({
   path: '/getHeader',
   method: 'GET',
@@ -91,9 +60,6 @@ const TestRoutes = h.apiSpec({
   'api.v1.test': {
     post: PostTestRoute,
   },
-  'api.v1.test.optional': {
-    post: PostOptionalTestRoute,
-  },
   'api.v1.getheader': {
     get: HeaderGetTestRoute,
   },
@@ -139,23 +105,6 @@ const createTestServer = (port: number) => {
     }
   });
 
-  testApp.post('/test/optional/:id', (req, res) => {
-    const filteredReq = {
-      query: req.query,
-      params: req.params,
-      headers: req.headers,
-      body: req.body,
-    };
-    const params = E.getOrElseW((err) => {
-      throw new Error(JSON.stringify(err));
-    })(PostTestRoute.request.decode(filteredReq));
-    const response = PostTestRoute.response[200].encode({
-      ...params,
-      baz: true,
-    });
-    res.send(response);
-  });
-
   testApp.get(HeaderGetTestRoute.path, (req, res) => {
     res.send(
       HeaderGetTestRoute.response[200].encode({
@@ -293,22 +242,6 @@ describe('decodeExpecting', () => {
       'Could not decode response 200: [{"invalid":"response"}] due to error [Invalid value undefined supplied to : { id: number, foo: string, bar: number, baz: boolean }/id: number\nInvalid value undefined supplied to : { id: number, foo: string, bar: number, baz: boolean }/foo: string\nInvalid value undefined supplied to : { id: number, foo: string, bar: number, baz: boolean }/bar: number\nInvalid value undefined supplied to : { id: number, foo: string, bar: number, baz: boolean }/baz: boolean]',
     );
   });
-
-  it('does not modify inputs by dropping keys with undefined values', async () => {
-    const body = {
-      id: 1337,
-      foo: 'test',
-      bar: 42,
-      optional: { baz: true, qux: undefined },
-    };
-    await apiClient['api.v1.test.optional'].post(body).decodeExpecting(200);
-    assert.deepEqual(body, {
-      id: 1337,
-      foo: 'test',
-      bar: 42,
-      optional: { baz: true, qux: undefined },
-    });
-  });
 });
 
 describe('superagent', async () => {