diff --git a/locksmith/src/controllers/v2/claimController.ts b/locksmith/src/controllers/v2/claimController.ts
index 9958a56260a..13614708d2a 100644
--- a/locksmith/src/controllers/v2/claimController.ts
+++ b/locksmith/src/controllers/v2/claimController.ts
@@ -12,6 +12,7 @@ import { getTotalPurchasePriceInCrypto } from '../../utils/claim'
 const ClaimBody = z.object({
   data: z.string().optional(),
   recipient: z.string().optional(),
+  referrer: z.string().optional(),
   email: z
     .string()
     .email()
@@ -31,7 +32,9 @@ export const LOCKS_WITH_DISABLED_CLAIMS = [
  * @returns
  */
 export const claim: RequestHandler = async (request, response: Response) => {
-  const { data, recipient, email } = await ClaimBody.parseAsync(request.body)
+  const { data, recipient, email, referrer } = await ClaimBody.parseAsync(
+    request.body
+  )
   const network = Number(request.params.network)
   const lockAddress = normalizer.ethereumAddress(request.params.lockAddress)
 
@@ -160,6 +163,7 @@ export const claim: RequestHandler = async (request, response: Response) => {
       owner,
       network,
       data,
+      referrer,
       keyManager: email ? keyManagerAddress : owner,
     },
     async (_, transactionHash) => {
diff --git a/locksmith/src/fulfillment/dispatcher.ts b/locksmith/src/fulfillment/dispatcher.ts
index 2e1e60c8d1d..67a81f48921 100644
--- a/locksmith/src/fulfillment/dispatcher.ts
+++ b/locksmith/src/fulfillment/dispatcher.ts
@@ -374,10 +374,11 @@ export default class Dispatcher {
       network: number
       data?: string
       keyManager?: string
+      referrer?: string
     },
     cb?: (error: any, hash: string | null) => Promise<unknown>
   ) {
-    const { network, lockAddress, owner, data, keyManager } = options
+    const { network, lockAddress, owner, data, keyManager, referrer } = options
     const walletService = new WalletService(networks)
 
     // get any purchaser, as the address is not required here.
@@ -396,6 +397,7 @@ export default class Dispatcher {
           owner,
           data,
           keyManager,
+          referrer,
         },
         { maxFeePerGas, maxPriorityFeePerGas },
         cb
diff --git a/packages/unlock-js/CHANGELOG.md b/packages/unlock-js/CHANGELOG.md
index 9ecbb6bbdb1..b5df541b23c 100644
--- a/packages/unlock-js/CHANGELOG.md
+++ b/packages/unlock-js/CHANGELOG.md
@@ -1,5 +1,9 @@
 # Changes
 
+# 0.40.2
+
+- claim now supports a `referrer` param
+
 # 0.40.1
 
 - adding missing ABI for locksmiths
diff --git a/packages/unlock-js/openapi.yml b/packages/unlock-js/openapi.yml
index 47f5bdc1e94..122adeb217a 100644
--- a/packages/unlock-js/openapi.yml
+++ b/packages/unlock-js/openapi.yml
@@ -1665,6 +1665,9 @@ paths:
                 recipient:
                   type: string
                   description: Recipient address for key
+                referrer:
+                  type: string
+                  description: Referrer address used to mint. This may get overwritten.
 
       responses:
         200:
diff --git a/packages/unlock-js/package.json b/packages/unlock-js/package.json
index 0591c1b5b15..922265fa793 100644
--- a/packages/unlock-js/package.json
+++ b/packages/unlock-js/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@unlock-protocol/unlock-js",
-  "version": "0.40.1",
+  "version": "0.40.2",
   "description": "This module provides libraries to include Unlock APIs inside a Javascript application.",
   "main": "dist/index.js",
   "module": "dist/index.mjs",