diff --git a/contracts/DecentralizedAutonomousTrust.sol b/contracts/DecentralizedAutonomousTrust.sol
index cbee513b..7b2f438e 100644
--- a/contracts/DecentralizedAutonomousTrust.sol
+++ b/contracts/DecentralizedAutonomousTrust.sol
@@ -892,7 +892,7 @@ contract DecentralizedAutonomousTrust
         buySlopeNum * totalSupply(), totalSupply(),
         buySlopeDen
       );
-      /// Math: this if condition avoids a potential overflow
+      // Math: this if condition avoids a potential overflow
       if(exitFee <= reserve)
       {
         exitFee = 0;
@@ -938,7 +938,7 @@ contract DecentralizedAutonomousTrust
     }
     else
     {
-      require(false, "INVALID_STATE");
+      revert("INVALID_STATE");
     }
 
     emit Close(exitFee);
diff --git a/test/wiki/close/close.js b/test/wiki/close/close.js
index 962103b5..dd5945fb 100644
--- a/test/wiki/close/close.js
+++ b/test/wiki/close/close.js
@@ -40,7 +40,8 @@ contract("wiki / close / close", accounts => {
       contracts.dat.close({
         from: await contracts.dat.beneficiary(),
         value: "10000000000000000000000"
-      })
+      }),
+      "INVALID_STATE"
     );
   });
 });
diff --git a/test/wiki/close/init.js b/test/wiki/close/init.js
index 17d7419a..c35b61ae 100644
--- a/test/wiki/close/init.js
+++ b/test/wiki/close/init.js
@@ -24,6 +24,11 @@ contract("wiki / close / init", accounts => {
     assert.equal(state.toString(), constants.STATE.INIT);
   });
 
+  it("exitFee estimate is 0", async () => {
+    const fee = await contracts.dat.estimateExitFee(0);
+    assert.equal(fee, 0);
+  });
+
   describe("on close", () => {
     beforeEach(async () => {
       await contracts.dat.close({
diff --git a/test/wiki/close/run.js b/test/wiki/close/run.js
index 3cf155d6..b1ae213f 100644
--- a/test/wiki/close/run.js
+++ b/test/wiki/close/run.js
@@ -1,3 +1,5 @@
+const { tokens } = require("hardlydifficult-ethereum-contracts");
+
 const sleep = require("sleep");
 const BigNumber = require("bignumber.js");
 const {
@@ -163,4 +165,21 @@ contract("wiki / close / run", accounts => {
       );
     });
   });
+
+  describe("when reserve is high", () => {
+    beforeEach(async () => {
+      // Redeploy using an ERC-20
+      const token = await tokens.dai.deploy(web3, accounts[0]);
+      contracts = await deployDat(accounts, { currency: token.address });
+      await approveAll(contracts, accounts);
+      await token.mint(contracts.dat.address, constants.MAX_UINT, {
+        from: accounts[0]
+      });
+    });
+
+    it("exitFee is 0", async () => {
+      const exitFee = new BigNumber(await contracts.dat.estimateExitFee(0));
+      assert.equal(exitFee, 0);
+    });
+  });
 });