diff --git a/integration-tests/worker/CHANGELOG.md b/integration-tests/worker/CHANGELOG.md
index d165860c7..46f113e69 100644
--- a/integration-tests/worker/CHANGELOG.md
+++ b/integration-tests/worker/CHANGELOG.md
@@ -1,5 +1,12 @@
 # @openfn/integration-tests-worker
 
+## 1.0.59
+
+### Patch Changes
+
+- Updated dependencies [0cf7198]
+  - @openfn/ws-worker@1.6.4
+
 ## 1.0.58
 
 ### Patch Changes
diff --git a/integration-tests/worker/package.json b/integration-tests/worker/package.json
index 5db029a02..e4893869e 100644
--- a/integration-tests/worker/package.json
+++ b/integration-tests/worker/package.json
@@ -1,7 +1,7 @@
 {
   "name": "@openfn/integration-tests-worker",
   "private": true,
-  "version": "1.0.58",
+  "version": "1.0.59",
   "description": "Lightning WOrker integration tests",
   "author": "Open Function Group <admin@openfn.org>",
   "license": "ISC",
diff --git a/packages/lightning-mock/src/api-sockets.ts b/packages/lightning-mock/src/api-sockets.ts
index 6a4725c7d..2ece130af 100644
--- a/packages/lightning-mock/src/api-sockets.ts
+++ b/packages/lightning-mock/src/api-sockets.ts
@@ -392,7 +392,7 @@ const createSocketAPI = (
     evt: PhoenixEvent<StepStartPayload>
   ) {
     const { ref, join_ref, topic } = evt;
-    const { step_id, job_id, input_dataclip_id } = evt.payload;
+    const { step_id, job_id } = evt.payload;
 
     const [_, runId] = topic.split(':');
     if (!state.dataclips) {
@@ -414,11 +414,6 @@ const createSocketAPI = (
         status: 'error',
         response: 'no job_id',
       };
-    } else if (!input_dataclip_id) {
-      payload = {
-        status: 'error',
-        response: 'no input_dataclip_id',
-      };
     }
 
     ws.reply<StepStartReply>({
diff --git a/packages/lightning-mock/test/events/step-start.test.ts b/packages/lightning-mock/test/events/step-start.test.ts
index 3f1924905..9ed7f88f0 100644
--- a/packages/lightning-mock/test/events/step-start.test.ts
+++ b/packages/lightning-mock/test/events/step-start.test.ts
@@ -95,7 +95,7 @@ test.serial('error if no job_id', async (t) => {
   });
 });
 
-test.serial('error if no input_dataclip_id', async (t) => {
+test.serial('no error if no input_dataclip_id', async (t) => {
   return new Promise(async (done) => {
     const run = createRun();
 
@@ -103,15 +103,15 @@ test.serial('error if no input_dataclip_id', async (t) => {
 
     const event = {
       job_id: 'a',
-      step_id: 'r:a',
-      input_dataclip_id: undefined,
+      step_id: 'r:a'
     };
 
     const channel = await join(client, run.id);
 
-    channel.push(STEP_START, event).receive('error', () => {
-      t.pass('event rejected');
+    channel.push(STEP_START, event).receive('ok', () => {
+      t.pass('event accepted');
       done();
     });
   });
 });
+
diff --git a/packages/ws-worker/CHANGELOG.md b/packages/ws-worker/CHANGELOG.md
index aed7257a9..2674a05a1 100644
--- a/packages/ws-worker/CHANGELOG.md
+++ b/packages/ws-worker/CHANGELOG.md
@@ -1,5 +1,11 @@
 # ws-worker
 
+## 1.6.4
+
+### Patch Changes
+
+- 0cf7198: Do not send the input_dataclip_id in step:start if the dataclip was witheld
+
 ## 1.6.3
 
 ### Patch Changes
diff --git a/packages/ws-worker/package.json b/packages/ws-worker/package.json
index 01f167394..9456405ac 100644
--- a/packages/ws-worker/package.json
+++ b/packages/ws-worker/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@openfn/ws-worker",
-  "version": "1.6.3",
+  "version": "1.6.4",
   "description": "A Websocket Worker to connect Lightning to a Runtime Engine",
   "main": "dist/index.js",
   "type": "module",
diff --git a/packages/ws-worker/src/events/step-complete.ts b/packages/ws-worker/src/events/step-complete.ts
index 54918628d..5307ee2dd 100644
--- a/packages/ws-worker/src/events/step-complete.ts
+++ b/packages/ws-worker/src/events/step-complete.ts
@@ -64,6 +64,7 @@ export default async function onStepComplete(
     }
     evt.output_dataclip_id = dataclipId;
   } catch (e) {
+    state.withheldDataclips[dataclipId] = true;
     evt.output_dataclip_error = 'DATACLIP_TOO_LARGE';
 
     const time = (timestamp() - BigInt(10e6)).toString();
diff --git a/packages/ws-worker/src/events/step-start.ts b/packages/ws-worker/src/events/step-start.ts
index ad5523483..bcfa8aa6a 100644
--- a/packages/ws-worker/src/events/step-start.ts
+++ b/packages/ws-worker/src/events/step-start.ts
@@ -18,10 +18,14 @@ export default async function onStepStart(
 
   const input_dataclip_id = state.inputDataclips[event.jobId];
 
-  await sendEvent<StepStartPayload>(channel, STEP_START, {
+  const evt: StepStartPayload = {
     step_id: state.activeStep!,
     job_id: state.activeJob!,
-    input_dataclip_id,
     timestamp: timeInMicroseconds(event.time),
-  });
+  };
+  if (!state.withheldDataclips[input_dataclip_id]) {
+    evt.input_dataclip_id = input_dataclip_id;
+  }
+
+  await sendEvent<StepStartPayload>(channel, STEP_START, evt);
 }
diff --git a/packages/ws-worker/src/types.d.ts b/packages/ws-worker/src/types.d.ts
index a9d09fbeb..974a79439 100644
--- a/packages/ws-worker/src/types.d.ts
+++ b/packages/ws-worker/src/types.d.ts
@@ -14,6 +14,8 @@ export type RunState = {
   // For each run, map the input ids
   // TODO better name maybe?
   inputDataclips: Record<string, string>;
+  // If for any reason a dataclip was not sent to lightning, track it
+  withheldDataclips: Record<string, true>;
   reasons: Record<string, ExitReason>;
 
   // final dataclip id
diff --git a/packages/ws-worker/src/util/create-run-state.ts b/packages/ws-worker/src/util/create-run-state.ts
index 460a28027..bb30fa05a 100644
--- a/packages/ws-worker/src/util/create-run-state.ts
+++ b/packages/ws-worker/src/util/create-run-state.ts
@@ -6,6 +6,7 @@ export default (plan: ExecutionPlan, input?: Lazy<State>): RunState => {
     lastDataclipId: '',
     dataclips: {},
     inputDataclips: {},
+    withheldDataclips: {},
     reasons: {},
     plan,
     input,
diff --git a/packages/ws-worker/src/util/timestamp.ts b/packages/ws-worker/src/util/timestamp.ts
index bc78e3fb7..d49d209ae 100644
--- a/packages/ws-worker/src/util/timestamp.ts
+++ b/packages/ws-worker/src/util/timestamp.ts
@@ -1,2 +1,4 @@
+import { TimeInMicroSeconds } from '@openfn/lexicon/lightning';
+
 export const timeInMicroseconds = (time?: bigint) =>
-  time && (BigInt(time) / BigInt(1e3)).toString();
+  (time && (BigInt(time) / BigInt(1e3)).toString()) as TimeInMicroSeconds;
diff --git a/packages/ws-worker/test/events/step-complete.test.ts b/packages/ws-worker/test/events/step-complete.test.ts
index ef4d6f42c..4cc53c750 100644
--- a/packages/ws-worker/test/events/step-complete.test.ts
+++ b/packages/ws-worker/test/events/step-complete.test.ts
@@ -206,6 +206,9 @@ test('do not include dataclips in step:complete if output_dataclip is too big',
   const channel = mockChannel({
     [RUN_LOG]: () => true,
     [STEP_COMPLETE]: (evt: StepCompletePayload) => {
+      const clipId = state.inputDataclips['a'];
+      t.true(state.withheldDataclips[clipId])
+
       t.falsy(evt.output_dataclip_id);
       t.falsy(evt.output_dataclip);
       t.is(evt.output_dataclip_error, 'DATACLIP_TOO_LARGE');
diff --git a/packages/ws-worker/test/events/step-start.test.ts b/packages/ws-worker/test/events/step-start.test.ts
index c75a1034f..b35099526 100644
--- a/packages/ws-worker/test/events/step-start.test.ts
+++ b/packages/ws-worker/test/events/step-start.test.ts
@@ -60,6 +60,40 @@ test('send a step:start event', async (t) => {
   await handleStepStart({ channel, state } as any, event);
 });
 
+test('if the input dataclip was withheld, do not send it', async (t) => {
+  const plan = {
+    id: 'run-1',
+    workflow: {
+      steps: [
+        { id: 'job-1', expression: '.' },
+        { id: 'job-2', expression: '.' },
+      ],
+    },
+    options: {},
+  };
+  const input = 'abc';
+  const jobId = 'job-1';
+
+  const state = createRunState(plan, input);
+  state.activeJob = jobId;
+  state.activeStep = 'b';
+  
+  // register and withhold the dataclip
+  state.withheldDataclips['abc'] = true
+  state.inputDataclips[jobId] = 'abc';
+
+  const channel = mockChannel({
+    [STEP_START]: (evt) => {
+      t.falsy(evt.input_dataclip_id, input);
+      return true;
+    },
+    [RUN_LOG]: () => true,
+  });
+
+  const event = { jobId } as any;
+  await handleStepStart({ channel, state } as any, event);
+});
+
 test('should include a timestamp', async (t) => {
   const plan = {
     id: 'run-1',