diff --git a/multichain-testing/test/fast-usdc/config.ts b/multichain-testing/test/fast-usdc/config.ts
index c7b1833ec6da..a53c5e5f66cb 100644
--- a/multichain-testing/test/fast-usdc/config.ts
+++ b/multichain-testing/test/fast-usdc/config.ts
@@ -1,4 +1,5 @@
 import type { IBCChannelID } from '@agoric/vats';
+import type { FeedPolicy } from '@agoric/fast-usdc/src/types.js';
 
 export const oracleMnemonics = {
   oracle1:
@@ -10,19 +11,12 @@ export const oracleMnemonics = {
 };
 harden(oracleMnemonics);
 
-export const makeFeedPolicy = (nobleAgoricChannelId: IBCChannelID) => {
+export const makeFeedPolicy = (
+  nobleAgoricChannelId: IBCChannelID,
+): Omit<FeedPolicy, 'chainPolicies'> => {
   return {
     nobleAgoricChannelId,
     nobleDomainId: 4,
-    chainPolicies: {
-      Arbitrum: {
-        attenuatedCttpBridgeAddress:
-          '0xe298b93ffB5eA1FB628e0C0D55A43aeaC268e347',
-        cctpTokenMessengerAddress: '0x19330d10D9Cc8751218eaf51E8885D058642E08A',
-        chainId: 42161,
-        confirmations: 2,
-      },
-    },
   };
 };
 harden(makeFeedPolicy);
diff --git a/packages/boot/test/fast-usdc/fast-usdc.test.ts b/packages/boot/test/fast-usdc/fast-usdc.test.ts
index f0692aba0fd1..796827714ac8 100644
--- a/packages/boot/test/fast-usdc/fast-usdc.test.ts
+++ b/packages/boot/test/fast-usdc/fast-usdc.test.ts
@@ -153,12 +153,12 @@ test.serial(
   },
 );
 
-test.serial('writes feed policy to vstorage', async t => {
+test.serial('writes chain policy to vstorage', async t => {
   const { storage } = t.context;
   const opts = {
     node: 'fastUsdc.feedPolicy',
     owner: 'the general and chain-specific policies for the Fast USDC feed',
-    showValue: JSON.parse,
+    showValue: defaultSerializer.parse,
   };
   await documentStorageSchema(t, storage, opts);
 });
diff --git a/packages/boot/test/fast-usdc/snapshots/fast-usdc.test.ts.md b/packages/boot/test/fast-usdc/snapshots/fast-usdc.test.ts.md
index 982534c91763..80d6379e2c87 100644
--- a/packages/boot/test/fast-usdc/snapshots/fast-usdc.test.ts.md
+++ b/packages/boot/test/fast-usdc/snapshots/fast-usdc.test.ts.md
@@ -4,7 +4,7 @@ The actual snapshot is saved in `fast-usdc.test.ts.snap`.
 
 Generated by [AVA](https://avajs.dev).
 
-## writes feed policy to vstorage
+## writes chain policy to vstorage
 
 > Under "published", the "fastUsdc.feedPolicy" node is delegated to the general and chain-specific policies for the Fast USDC feed.
 > The example below illustrates the schema of the data published there.
@@ -18,33 +18,43 @@ Generated by [AVA](https://avajs.dev).
           chainPolicies: {
             Arbitrum: {
               attenuatedCttpBridgeAddress: '0xe298b93ffB5eA1FB628e0C0D55A43aeaC268e347',
+              blockWindowSize: 10,
               cctpTokenMessengerAddress: '0x19330d10D9Cc8751218eaf51E8885D058642E08A',
               chainId: 42161,
               confirmations: 2,
+              maxAmountPerBlockWindow: 20000000000n,
             },
             Base: {
               attenuatedCttpBridgeAddress: '0xB6615B2662b35fc3533F8479002e62D0523341De',
+              blockWindowSize: 10,
               cctpTokenMessengerAddress: '0x1682Ae6375C4E4A97e4B583BC394c861A46D8962',
               chainId: 8453,
               confirmations: 2,
+              maxAmountPerBlockWindow: 20000000000n,
             },
             Ethereum: {
               attenuatedCttpBridgeAddress: '0xBC8552339dA68EB65C8b88B414B5854E0E366cFc',
+              blockWindowSize: 10,
               cctpTokenMessengerAddress: '0xBd3fa81B58Ba92a82136038B25aDec7066af3155',
               chainId: 1,
               confirmations: 2,
+              maxAmountPerBlockWindow: 20000000000n,
             },
             Optimism: {
               attenuatedCttpBridgeAddress: '0x48C5417ED570928eC85D5e3AD4e7E0EeD7dB1E2A',
+              blockWindowSize: 10,
               cctpTokenMessengerAddress: '0x2B4069517957735bE00ceE0fadAE88a26365528f',
               chainId: 10,
               confirmations: 2,
+              maxAmountPerBlockWindow: 20000000000n,
             },
             Polygon: {
               attenuatedCttpBridgeAddress: '0x32cb9574650AFF312c80edc4B4343Ff5500767cA',
+              blockWindowSize: 10,
               cctpTokenMessengerAddress: '0x9daF8c91AEFAE50b9c0E69629D3F6Ca40cA3B3FE',
               chainId: 137,
               confirmations: 2,
+              maxAmountPerBlockWindow: 20000000000n,
             },
           },
           nobleAgoricChannelId: 'channel-21',
diff --git a/packages/boot/test/fast-usdc/snapshots/fast-usdc.test.ts.snap b/packages/boot/test/fast-usdc/snapshots/fast-usdc.test.ts.snap
index 3b97e5ce3fdd..631c44c151fa 100644
Binary files a/packages/boot/test/fast-usdc/snapshots/fast-usdc.test.ts.snap and b/packages/boot/test/fast-usdc/snapshots/fast-usdc.test.ts.snap differ
diff --git a/packages/builders/scripts/fast-usdc/init-fast-usdc.js b/packages/builders/scripts/fast-usdc/init-fast-usdc.js
index fade01cea83f..28f7bb21df07 100644
--- a/packages/builders/scripts/fast-usdc/init-fast-usdc.js
+++ b/packages/builders/scripts/fast-usdc/init-fast-usdc.js
@@ -122,7 +122,15 @@ export default async (homeP, endowments) => {
       return configurations[net].feedPolicy;
     }
     if (!feedPolicy) throw Error(feedPolicyUsage);
-    return JSON.parse(feedPolicy);
+    const parsed = JSON.parse(feedPolicy);
+    if (!parsed.chainPolicies) {
+      // chainPolicies contain bigints which can't be stringified
+      return {
+        // @ts-expect-error spreading CopyRecord & Passable
+        ...configurations.MAINNET.feedPolicy,
+        ...parsed,
+      };
+    }
   };
 
   const parseOracleArgs = () => {
diff --git a/packages/fast-usdc/src/fast-usdc-policy.core.js b/packages/fast-usdc/src/fast-usdc-policy.core.js
index 1a8af06d5ac1..a92d9fdb2b89 100644
--- a/packages/fast-usdc/src/fast-usdc-policy.core.js
+++ b/packages/fast-usdc/src/fast-usdc-policy.core.js
@@ -3,6 +3,7 @@
 import { E } from '@endo/far';
 import { fromExternalConfig } from './utils/config-marshal.js';
 import { FeedPolicyShape } from './type-guards.js';
+import { makePublishingStorageKit } from './fast-usdc.start.js';
 
 /**
  * @import {Passable} from '@endo/pass-style'
@@ -18,11 +19,13 @@ const FEED_POLICY = 'feedPolicy';
  * XXX copied from fast-usdc.start.js
  *
  * @param {ERef<StorageNode>} node
- * @param {FeedPolicy} policy
+ * @param {ERef<Marshaller>} marshaller
+ * @param {FeedPolicy & Passable} policy
  */
-const publishFeedPolicy = async (node, policy) => {
+const publishFeedPolicy = async (node, marshaller, policy) => {
   const feedPolicy = E(node).makeChildNode(FEED_POLICY);
-  await E(feedPolicy).setValue(JSON.stringify(policy));
+  const value = await E(marshaller).toCapData(policy);
+  await E(feedPolicy).setValue(JSON.stringify(value));
 };
 
 /**
@@ -32,7 +35,7 @@ const publishFeedPolicy = async (node, policy) => {
  * @param {{ options: LegibleCapData<{feedPolicy: FeedPolicy & Passable}> }} config
  */
 export const updateFastUsdcPolicy = async (
-  { consume: { agoricNames, chainStorage } },
+  { consume: { agoricNames, board, chainStorage } },
   config,
 ) => {
   /** @type {Issuer<'nat'>} */
@@ -46,9 +49,12 @@ export const updateFastUsdcPolicy = async (
     harden({ feedPolicy: FeedPolicyShape }),
   );
 
-  const storageNode = await E(chainStorage).makeChildNode(contractName);
+  const { storageNode, marshaller } = await makePublishingStorageKit(
+    contractName,
+    { board, chainStorage },
+  );
 
-  await publishFeedPolicy(storageNode, feedPolicy);
+  await publishFeedPolicy(storageNode, marshaller, feedPolicy);
 };
 
 /**
@@ -67,6 +73,7 @@ export const getManifestForUpdateFastUsdcPolicy = (_utils, { options }) => {
 
           // widely shared: name services
           agoricNames: true,
+          board: true,
         },
       },
     },
diff --git a/packages/fast-usdc/src/fast-usdc.start.js b/packages/fast-usdc/src/fast-usdc.start.js
index 44a2838a1307..8e38f8a4fc62 100644
--- a/packages/fast-usdc/src/fast-usdc.start.js
+++ b/packages/fast-usdc/src/fast-usdc.start.js
@@ -22,6 +22,7 @@ import { fromExternalConfig } from './utils/config-marshal.js';
  * @import {Board} from '@agoric/vats'
  * @import {ManifestBundleRef} from '@agoric/deploy-script-support/src/externalTypes.js'
  * @import {BootstrapManifest} from '@agoric/vats/src/core/lib-boot.js'
+ * @import {Passable} from '@endo/pass-style'
  * @import {LegibleCapData} from './utils/config-marshal.js'
  * @import {FastUsdcSF} from './fast-usdc.contract.js'
  * @import {FeedPolicy, FastUSDCConfig} from './types.js'
@@ -57,7 +58,10 @@ export const FastUSDCConfigShape = M.splitRecord({
  *   board: ERef<Board>;
  * }} io
  */
-const makePublishingStorageKit = async (path, { chainStorage, board }) => {
+export const makePublishingStorageKit = async (
+  path,
+  { chainStorage, board },
+) => {
   const storageNode = await E(chainStorage).makeChildNode(path);
 
   const marshaller = await E(board).getPublishingMarshaller();
@@ -89,11 +93,13 @@ const POOL_METRICS = 'poolMetrics';
 
 /**
  * @param {ERef<StorageNode>} node
- * @param {FeedPolicy} policy
+ * @param {ERef<Marshaller>} marshaller
+ * @param {FeedPolicy & Passable} policy
  */
-const publishFeedPolicy = async (node, policy) => {
+const publishFeedPolicy = async (node, marshaller, policy) => {
   const feedPolicy = E(node).makeChildNode(FEED_POLICY);
-  await E(feedPolicy).setValue(JSON.stringify(policy));
+  const value = await E(marshaller).toCapData(policy);
+  await E(feedPolicy).setValue(JSON.stringify(value));
 };
 
 /**
@@ -211,7 +217,7 @@ export const startFastUSDC = async (
   fastUsdcKit.resolve(harden({ ...kit, privateArgs }));
   const { instance, creatorFacet } = kit;
 
-  await publishFeedPolicy(storageNode, feedPolicy);
+  await publishFeedPolicy(storageNode, marshaller, feedPolicy);
 
   const {
     issuers: fastUsdcIssuers,
diff --git a/packages/fast-usdc/src/type-guards.js b/packages/fast-usdc/src/type-guards.js
index ccbb596ae327..e6b801b65c7a 100644
--- a/packages/fast-usdc/src/type-guards.js
+++ b/packages/fast-usdc/src/type-guards.js
@@ -122,9 +122,11 @@ harden(PoolMetricsShape);
 /** @type {TypedPattern<ChainPolicy>} */
 export const ChainPolicyShape = {
   attenuatedCttpBridgeAddress: EvmHashShape,
+  blockWindowSize: M.number(),
   cctpTokenMessengerAddress: EvmHashShape,
   confirmations: M.number(),
   chainId: M.number(),
+  maxAmountPerBlockWindow: M.bigint(),
 };
 harden(ChainPolicyShape);
 
diff --git a/packages/fast-usdc/src/types.ts b/packages/fast-usdc/src/types.ts
index 433ea135d978..cce645843aaf 100644
--- a/packages/fast-usdc/src/types.ts
+++ b/packages/fast-usdc/src/types.ts
@@ -83,12 +83,16 @@ export interface PoolMetrics extends PoolStats {
 export interface ChainPolicy {
   /** `msg.sender` of DepositAndBurn to TokenMessenger must be an attenuated wrapper contract that does not contain `replaceDepositForBurn` */
   attenuatedCttpBridgeAddress: EvmHash;
+  /** the number of blocks to consider for `maxAmountPerBlockWindow` */
+  blockWindowSize: number;
   /** @see {@link https://developers.circle.com/stablecoins/evm-smart-contracts} */
   cctpTokenMessengerAddress: EvmHash;
   /** e.g., `1` for ETH mainnet 42161 for Arbitrum One. @see {@link https://chainlist.org/} */
   chainId: EvmChainID;
   /** the number of block confirmations to observe before reporting */
   confirmations: number;
+  /** do not advance more than this amount per block window */
+  maxAmountPerBlockWindow: bigint;
 }
 
 export interface FeedPolicy {
diff --git a/packages/fast-usdc/src/utils/chain-policies.js b/packages/fast-usdc/src/utils/chain-policies.js
index a9020615ed84..7ce3098ad14f 100644
--- a/packages/fast-usdc/src/utils/chain-policies.js
+++ b/packages/fast-usdc/src/utils/chain-policies.js
@@ -5,70 +5,90 @@ export const ChainPolicies = /** @type {const} */ ({
   MAINNET: {
     Arbitrum: {
       attenuatedCttpBridgeAddress: '0xe298b93ffB5eA1FB628e0C0D55A43aeaC268e347',
+      blockWindowSize: 10,
       cctpTokenMessengerAddress: '0x19330d10D9Cc8751218eaf51E8885D058642E08A',
       chainId: 42161,
-      confirmations: 2,
+      confirmations: 2, // TODO mocked
+      maxAmountPerBlockWindow: 20_000_000_000n, // TODO mocked
     },
     Base: {
       attenuatedCttpBridgeAddress: '0xB6615B2662b35fc3533F8479002e62D0523341De',
+      blockWindowSize: 10,
       cctpTokenMessengerAddress: '0x1682Ae6375C4E4A97e4B583BC394c861A46D8962',
       chainId: 8453,
-      confirmations: 2,
+      confirmations: 2, // TODO mocked
+      maxAmountPerBlockWindow: 20_000_000_000n, // TODO mocked
     },
     Ethereum: {
       attenuatedCttpBridgeAddress: '0xBC8552339dA68EB65C8b88B414B5854E0E366cFc',
+      blockWindowSize: 10,
       cctpTokenMessengerAddress: '0xBd3fa81B58Ba92a82136038B25aDec7066af3155',
       chainId: 1,
-      confirmations: 2,
+      confirmations: 2, // TODO mocked
+      maxAmountPerBlockWindow: 20_000_000_000n, // TODO mocked
     },
     Optimism: {
       attenuatedCttpBridgeAddress: '0x48C5417ED570928eC85D5e3AD4e7E0EeD7dB1E2A',
+      blockWindowSize: 10,
       cctpTokenMessengerAddress: '0x2B4069517957735bE00ceE0fadAE88a26365528f',
       chainId: 10,
-      confirmations: 2,
+      confirmations: 2, // TODO mocked
+      maxAmountPerBlockWindow: 20_000_000_000n, // TODO mocked
     },
     Polygon: {
       attenuatedCttpBridgeAddress: '0x32cb9574650AFF312c80edc4B4343Ff5500767cA',
+      blockWindowSize: 10,
       cctpTokenMessengerAddress: '0x9daF8c91AEFAE50b9c0E69629D3F6Ca40cA3B3FE',
       chainId: 137,
-      confirmations: 2,
+      confirmations: 2, // TODO mocked
+      maxAmountPerBlockWindow: 20_000_000_000n, // TODO mocked
     },
   },
   TESTNET: {
     // Arbitrum Sepolia
     Arbitrum: {
       attenuatedCttpBridgeAddress: '0xTODO',
+      blockWindowSize: 10,
       cctpTokenMessengerAddress: '0x9f3B8679c73C2Fef8b59B4f3444d4e156fb70AA5',
       chainId: 421614,
       confirmations: 2,
+      maxAmountPerBlockWindow: 20_000_000_000n,
     },
     // Base Sepolia
     Base: {
       attenuatedCttpBridgeAddress: '0xTODO',
+      blockWindowSize: 10,
       cctpTokenMessengerAddress: '0x9f3B8679c73C2Fef8b59B4f3444d4e156fb70AA5',
       chainId: 84532,
       confirmations: 2,
+      maxAmountPerBlockWindow: 20_000_000_000n,
     },
     // Ethereum Sepolia
     Ethereum: {
       attenuatedCttpBridgeAddress: '0xTODO',
+      blockWindowSize: 10,
       cctpTokenMessengerAddress: '0x9f3B8679c73C2Fef8b59B4f3444d4e156fb70AA5',
       chainId: 11155111,
       confirmations: 2,
+      maxAmountPerBlockWindow: 20_000_000_000n,
     },
     // OP Sepolia
     Optimism: {
       attenuatedCttpBridgeAddress: '0xTODO',
+      blockWindowSize: 10,
       cctpTokenMessengerAddress: '0x9f3B8679c73C2Fef8b59B4f3444d4e156fb70AA5',
       chainId: 11155420,
       confirmations: 2,
+      maxAmountPerBlockWindow: 20_000_000_000n,
     },
     // Polygon PoS Amoy
     Polygon: {
       attenuatedCttpBridgeAddress: '0xTODO',
+      blockWindowSize: 10,
       cctpTokenMessengerAddress: '0x9f3B8679c73C2Fef8b59B4f3444d4e156fb70AA5',
       chainId: 80002,
       confirmations: 2,
+      maxAmountPerBlockWindow: 20_000_000_000n,
     },
   },
 });