diff --git a/solidity/core/test/validator-manager/inboxMultisigValidatorManager.test.ts b/solidity/core/test/validator-manager/inboxMultisigValidatorManager.test.ts
index e69de29bb..c4c5387d3 100644
--- a/solidity/core/test/validator-manager/inboxMultisigValidatorManager.test.ts
+++ b/solidity/core/test/validator-manager/inboxMultisigValidatorManager.test.ts
@@ -0,0 +1,97 @@
+import { ethers } from 'hardhat';
+import { Validator } from '@abacus-network/utils';
+import { SignerWithAddress } from '@nomiclabs/hardhat-ethers/signers';
+
+import {
+  Inbox,
+  Inbox__factory,
+  InboxMultisigValidatorManager,
+  InboxMultisigValidatorManager__factory,
+} from '../../types';
+import { getCheckpointSignatures } from './utils';
+import { expect } from 'chai';
+
+const OUTBOX_DOMAIN = 1234;
+const INBOX_DOMAIN = 4321;
+const QUORUM_THRESHOLD = 2;
+
+describe.only('InboxMultisigValidatorManager', () => {
+  let validatorManager: InboxMultisigValidatorManager,
+    inbox: Inbox,
+    signer: SignerWithAddress,
+    validator0: Validator,
+    validator1: Validator;
+
+  before(async () => {
+    const signers = await ethers.getSigners();
+    [signer] = signers;
+    const [
+      ,
+      validatorSigner0,
+      validatorSigner1,
+    ] = signers;
+    validator0 = await Validator.fromSigner(validatorSigner0, OUTBOX_DOMAIN);
+    validator1 = await Validator.fromSigner(validatorSigner1, OUTBOX_DOMAIN);
+  });
+
+  beforeEach(async () => {
+    const validatorManagerFactory = new InboxMultisigValidatorManager__factory(
+      signer,
+    );
+    validatorManager = await validatorManagerFactory.deploy(
+      OUTBOX_DOMAIN,
+      [validator0.address, validator1.address],
+      QUORUM_THRESHOLD,
+    );
+
+    const inboxFactory = new Inbox__factory(signer);
+    inbox = await inboxFactory.deploy(INBOX_DOMAIN);
+    await inbox.initialize(
+      OUTBOX_DOMAIN,
+      validatorManager.address,
+      ethers.constants.HashZero,
+      0,
+    );
+  });
+
+  describe('#checkpoint', () => {
+    const root = ethers.utils.formatBytes32String('test root');
+    const index = 1;
+
+    it('submits a checkpoint to the Inbox if there is a quorum', async () => {
+      const signatures = await getCheckpointSignatures(
+        root,
+        index,
+        [validator0, validator1], // 2/2 signers, making a quorum
+      );
+
+      await validatorManager.checkpoint(
+        inbox.address,
+        root,
+        index,
+        signatures,
+      );
+      
+      expect(
+        await inbox.checkpoints(root)
+      ).to.equal(index);
+    });
+
+    it('reverts if there is not a quorum', async () => {
+      const signatures = await getCheckpointSignatures(
+        root,
+        index,
+        [validator0], // 1/2 signer is not a quorum
+      );
+
+      await expect(
+        validatorManager.checkpoint(
+          inbox.address,
+          root,
+          index,
+          signatures,
+        )
+      ).to.be.revertedWith('!quorum');
+    });
+  });
+});