diff --git a/src/js/ripple/orderbook.js b/src/js/ripple/orderbook.js
index b43643a518..98db75cc17 100644
--- a/src/js/ripple/orderbook.js
+++ b/src/js/ripple/orderbook.js
@@ -43,8 +43,9 @@ function OrderBook(remote, getsC, getsI, paysC, paysI, key) {
   this._shouldSubscribe = true;
   this._listeners = 0;
   this._offers = [ ];
-  this._ownerFunds = { };
   this._offerCounts = { };
+  this._ownerFunds = { };
+  this._ownerOffers = { };
 
   // We consider ourselves synchronized if we have a current
   // copy of the offers, we are online and subscribed to updates.
@@ -180,6 +181,7 @@ OrderBook.prototype.unsubscribe = function() {
 
 OrderBook.prototype.resetCache = function() {
   this._ownerFunds = { };
+  this._ownerOffers = { };
   this._offerCounts = { };
   this._synchronized = false;
 };
@@ -232,6 +234,8 @@ OrderBook.prototype.removeCachedFunds = function(account) {
 
 /**
  * Get offer count for offer owner
+ *
+ * @param {String} account address
  */
 
 OrderBook.prototype.getOfferCount = function(account) {
@@ -241,6 +245,8 @@ OrderBook.prototype.getOfferCount = function(account) {
 
 /**
  * Increment offer count for offer owner
+ *
+ * @param {String} account address
  */
 
 OrderBook.prototype.incrementOfferCount = function(account) {
@@ -252,6 +258,8 @@ OrderBook.prototype.incrementOfferCount = function(account) {
 
 /**
  * Decrement offer count for offer owner
+ *
+ * @param {String} account address
  */
 
 OrderBook.prototype.decrementOfferCount = function(account) {
@@ -261,6 +269,56 @@ OrderBook.prototype.decrementOfferCount = function(account) {
   return result;
 };
 
+/**
+ * Add offer amount to sum amount being offered by an account
+ *
+ * @param {String} account address
+ * @param {Object|String} offer amount
+ * @return sum
+ */
+
+OrderBook.prototype.addOwnerOffer = function(account, amount) {
+  assert(UInt160.is_valid(account), 'Account is invalid');
+  var previousAmount = this.getOwnerOfferSum(account);
+  var newAmount = previousAmount.add(Amount.from_json(amount));
+  this._ownerOffers[account] = newAmount;
+  return newAmount;
+};
+
+/**
+ * Subtract offer amount from sum amount being offered by an account
+ *
+ * @param {String} account address
+ * @param {Object|String} offer amount
+ * @return sum
+ */
+
+OrderBook.prototype.subtractOwnerOffer = function(account, amount) {
+  assert(UInt160.is_valid(account), 'Account is invalid');
+  this._ownerOffers[account].subtract(Amount.from_json(amount));
+  return this._ownerOffers[account];
+};
+
+/**
+ * Get sum amount for offers by an account
+ *
+ * @param {String} account address
+ * @return sum
+ */
+
+OrderBook.prototype.getOwnerOfferSum = function(account) {
+  assert(UInt160.is_valid(account), 'Account is invalid');
+  var amount = this._ownerOffers[account];
+  if (!amount) {
+    if (typeof amount === 'string') {
+      amount = Amount.from_json('0');
+    } else {
+      amount = Amount.from_json('0' + OrderBook.IOU_SUFFIX);
+    }
+  }
+  return amount;
+};
+
 /**
  * Compute funded amount for a balance/transferRate
  *
@@ -358,11 +416,20 @@ OrderBook.prototype.setFundedAmount = function(offer, fundedAmount) {
     return offer;
   }
 
+  // Sum of offer amounts by an account
+  var offerSum = this.getOwnerOfferSum(offer.Account);
+
+  if (offerSum.is_zero()) {
+    // If there are no cached offer amounts for the account, default to
+    // TakerGets of this offer
+    offerSum = Amount.from_json(offer.TakerGets);
+  }
+
   offer.is_fully_funded = Amount.from_json(
     this._currencyGets.is_native()
     ? fundedAmount
     : fundedAmount + OrderBook.IOU_SUFFIX
-  ).compareTo(Amount.from_json(offer.TakerGets)) >= 0;
+  ).compareTo(offerSum) >= 0;
 
   if (offer.is_fully_funded) {
     offer.taker_gets_funded = Amount.from_json(offer.TakerGets).to_text();
@@ -376,12 +443,8 @@ OrderBook.prototype.setFundedAmount = function(offer, fundedAmount) {
   ? offer.TakerPays.value
   : offer.TakerPays;
 
-  var takerGetsValue = (typeof offer.TakerGets === 'object')
-  ? offer.TakerGets.value
-  : offer.TakerGets;
-
   var takerPays = Amount.from_json(takerPaysValue +  OrderBook.IOU_SUFFIX);
-  var takerGets = Amount.from_json(takerGetsValue + OrderBook.IOU_SUFFIX);
+  var takerGets = Amount.from_json(offerSum);
   var fundedPays = Amount.from_json(fundedAmount + OrderBook.IOU_SUFFIX);
   var rate = takerPays.divide(takerGets);
 
@@ -662,9 +725,16 @@ OrderBook.offerRewrite = function(offer) {
 OrderBook.prototype.setOffers = function(offers) {
   assert(Array.isArray(offers));
 
+  var l = offers.length;
   var newOffers = [ ];
 
-  for (var i=0, l=offers.length; i<l; i++) {
+  for (var i=0; i<l; i++) {
+    var offer = offers[i];
+    // Add offer amount to sum for account
+    this.addOwnerOffer(offer.Account, offer.TakerGets);
+  }
+
+  for (var i=0; i<l; i++) {
     var offer = OrderBook.offerRewrite(offers[i]);
     var fundedAmount;
 
@@ -675,8 +745,8 @@ OrderBook.prototype.setOffers = function(offers) {
       this.addCachedFunds(offer.Account, fundedAmount);
     }
 
-    this.setFundedAmount(offer, fundedAmount);
     this.incrementOfferCount(offer.Account);
+    this.setFundedAmount(offer, fundedAmount);
 
     newOffers.push(offer);
   }
@@ -888,6 +958,9 @@ OrderBook.prototype.insertOffer = function(node, fundedAmount) {
     log.info('inserting offer', this._key, node.fields);
   }
 
+  // Add offer amount to sum for account
+  this.addOwnerOffer(node.fields.Account, node.fields.TakerGets);
+
   var nodeFields = OrderBook.offerRewrite(node.fields);
   nodeFields.LedgerEntryType = node.entryType;
   nodeFields.index = node.ledgerIndex;
@@ -904,7 +977,7 @@ OrderBook.prototype.insertOffer = function(node, fundedAmount) {
   // XXX Should use Amount#from_quality
   var price = Amount.from_json(
     nodeFields.TakerPays
-  ).ratio_human(node.fields.TakerGets, DATE_REF);
+  ).ratio_human(nodeFields.TakerGets, DATE_REF);
 
   for (var i=0, l=this._offers.length; i<l; i++) {
     var offer = this._offers[i];
@@ -944,14 +1017,21 @@ OrderBook.prototype.modifyOffer = function(node, isDeletedNode) {
     var offer = this._offers[i];
     if (offer.index === node.ledgerIndex) {
       if (isDeletedNode) {
-        // Multiple offers same account?
+        // Remove offer amount from sum for account
+        this.subtractOwnerOffer(offer.Account, offer.TakerGets);
         this._offers.splice(i, 1);
         this.emit('offer_removed', offer);
       } else {
         // TODO: This assumes no fields are deleted, which is
         // probably a safe assumption, but should be checked.
-        var previousOffer = extend({}, offer);
+        var previousOffer = extend({ }, offer);
         extend(offer, node.fieldsFinal);
+
+        // Remove offer amount from sum for account
+        this.subtractOwnerOffer(offer.Account, previousOffer.TakerGets);
+        // Add offer amount from sum for account
+        this.addOwnerOffer(offer.Account, offer.TakerGets);
+
         this.emit('offer_changed', previousOffer, offer);
       }
       break;
diff --git a/test/orderbook-test.js b/test/orderbook-test.js
index 103bc35575..a1b7b91d38 100644
--- a/test/orderbook-test.js
+++ b/test/orderbook-test.js
@@ -337,6 +337,7 @@ describe('OrderBook', function() {
     });
 
     var offer = {
+      Account: 'rrrrrrrrrrrrrrrrrrrrrhoLvTp',
       TakerGets: {
         value: '100',
         currency: 'BTC',
@@ -348,6 +349,7 @@ describe('OrderBook', function() {
     book.setFundedAmount(offer, '100.1234');
 
     var expected = {
+      Account: 'rrrrrrrrrrrrrrrrrrrrrhoLvTp',
       TakerGets: offer.TakerGets,
       TakerPays: offer.TakerPays,
       is_fully_funded: true,
@@ -367,6 +369,7 @@ describe('OrderBook', function() {
     });
 
     var offer = {
+      Account: 'rrrrrrrrrrrrrrrrrrrrrhoLvTp',
       TakerGets: {
         value: '100',
         currency: 'BTC',
@@ -378,6 +381,7 @@ describe('OrderBook', function() {
     book.setFundedAmount(offer, '99');
 
     var expected = {
+      Account: 'rrrrrrrrrrrrrrrrrrrrrhoLvTp',
       TakerGets: offer.TakerGets,
       TakerPays: offer.TakerPays,
       is_fully_funded: false,
@@ -397,6 +401,7 @@ describe('OrderBook', function() {
     });
 
     var offer = {
+      Account: 'rrrrrrrrrrrrrrrrrrrrrhoLvTp',
       TakerGets: '100',
       TakerPays: {
         value: '123.456',
@@ -408,6 +413,7 @@ describe('OrderBook', function() {
     book.setFundedAmount(offer, '100.1');
 
     var expected = {
+      Account: 'rrrrrrrrrrrrrrrrrrrrrhoLvTp',
       TakerGets: offer.TakerGets,
       TakerPays: offer.TakerPays,
       is_fully_funded: true,
@@ -427,6 +433,7 @@ describe('OrderBook', function() {
     });
 
     var offer = {
+      Account: 'rrrrrrrrrrrrrrrrrrrrrhoLvTp',
       TakerGets: '100',
       TakerPays: {
         value: '123.456',
@@ -438,6 +445,7 @@ describe('OrderBook', function() {
     book.setFundedAmount(offer, '99');
 
     var expected = {
+      Account: 'rrrrrrrrrrrrrrrrrrrrrhoLvTp',
       TakerGets: offer.TakerGets,
       TakerPays: offer.TakerPays,
       is_fully_funded: false,
@@ -457,6 +465,7 @@ describe('OrderBook', function() {
     });
 
     var offer = {
+      Account: 'rrrrrrrrrrrrrrrrrrrrrhoLvTp',
       TakerGets: {
         value: '100',
         currency: 'BTC',
@@ -468,6 +477,7 @@ describe('OrderBook', function() {
     book.setFundedAmount(offer, '0');
 
     assert.deepEqual(offer, {
+      Account: 'rrrrrrrrrrrrrrrrrrrrrhoLvTp',
       TakerGets: offer.TakerGets,
       TakerPays: offer.TakerPays,
       is_fully_funded: false,
@@ -1450,6 +1460,56 @@ describe('OrderBook', function() {
       index: 'A437D85DF80D250F79308F2B613CF5391C7CF8EE9099BC4E553942651CD9FA86',
       owner_funds: '0.950363009783092',
       quality: '498.6116758238228'
+    },
+    {
+      Account: 'rwBG69mujDoD5yQfL3Sf7Yuh7rUNYdxe9Y',
+      BookDirectory: '6EAB7C172DEFA430DBFAD120FDC373B5F5AF8B191649EC985711B6D8C62EF414',
+      BookNode: '0000000000000000',
+      Expiration: 461498565,
+      Flags: 131072,
+      LedgerEntryType: 'Offer',
+      OwnerNode: '0000000000000144',
+      PreviousTxnID: 'C8296B9CCA6DC594C7CD271C5D8FD11FEE380021A07768B25935642CDB37048A',
+      PreviousTxnLgrSeq: 8342469,
+      Sequence: 29356,
+      TakerGets: {
+        currency: 'BTC',
+        issuer: 'rvYAfWj5gh67oV6fW32ZzP3Aw4Eubs59B',
+        value: '0.5'
+      },
+      TakerPays: {
+        currency: 'USD',
+        issuer: 'rvYAfWj5gh67oV6fW32ZzP3Aw4Eubs59B',
+        value: '99.72233516476456'
+      },
+      index: 'A437D85DF80D250F79308F2B613CF5391C7CF8EE9099BC4E553942651CD9FA86',
+      owner_funds: '0.950363009783092',
+      quality: '498.6116758238228'
+    },
+    {
+      Account: 'rwBG69mujDoD5yQfL3Sf7Yuh7rUNYdxe9Y',
+      BookDirectory: '6EAB7C172DEFA430DBFAD120FDC373B5F5AF8B191649EC985711B6D8C62EF414',
+      BookNode: '0000000000000000',
+      Expiration: 461498565,
+      Flags: 131078,
+      LedgerEntryType: 'Offer',
+      OwnerNode: '0000000000000144',
+      PreviousTxnID: 'C8296B9CCA6DC594C7CD271C5D8FD11FEE380021A07768B25935642CDB37048A',
+      PreviousTxnLgrSeq: 8342469,
+      Sequence: 29354,
+      TakerGets: {
+        currency: 'BTC',
+        issuer: 'rvYAfWj5gh67oV6fW32ZzP3Aw4Eubs59B',
+        value: '0.5'
+      },
+      TakerPays: {
+        currency: 'USD',
+        issuer: 'rvYAfWj5gh67oV6fW32ZzP3Aw4Eubs59B',
+        value: '99.72233516476456'
+      },
+      index: 'A437D85DF80D250F79308F2B613CF5391C7CF8EE9099BC4E553942651CD9FA86',
+      owner_funds: '0.950363009783092',
+      quality: '498.6116758238228'
     }
     ]
   };
@@ -1533,7 +1593,53 @@ describe('OrderBook', function() {
         is_fully_funded: true,
         taker_gets_funded: '0.2',
         taker_pays_funded: '99.72233516476456'
-      }
+      },
+      { Account: 'rwBG69mujDoD5yQfL3Sf7Yuh7rUNYdxe9Y',
+        BookDirectory: '6EAB7C172DEFA430DBFAD120FDC373B5F5AF8B191649EC985711B6D8C62EF414',
+        BookNode: '0000000000000000',
+        Expiration: 461498565,
+        Flags: 131072,
+        LedgerEntryType: 'Offer',
+        OwnerNode: '0000000000000144',
+        Sequence: 29356,
+        TakerGets: { currency: 'BTC',
+          issuer: 'rvYAfWj5gh67oV6fW32ZzP3Aw4Eubs59B',
+          value: '0.5'
+        },
+        TakerPays: {
+          currency: 'USD',
+          issuer: 'rvYAfWj5gh67oV6fW32ZzP3Aw4Eubs59B',
+          value: '99.72233516476456'
+        },
+        index: 'A437D85DF80D250F79308F2B613CF5391C7CF8EE9099BC4E553942651CD9FA86',
+        owner_funds: '0.950363009783092',
+        is_fully_funded: false,
+        taker_gets_funded: '0.9484660776278363',
+        taker_pays_funded: '94.58325208561269' },
+        { Account: 'rwBG69mujDoD5yQfL3Sf7Yuh7rUNYdxe9Y',
+          BookDirectory: '6EAB7C172DEFA430DBFAD120FDC373B5F5AF8B191649EC985711B6D8C62EF414',
+          BookNode: '0000000000000000',
+          Expiration: 461498565,
+          Flags: 131078,
+          LedgerEntryType: 'Offer',
+          OwnerNode: '0000000000000144',
+          Sequence: 29354,
+          TakerGets: {
+            currency: 'BTC',
+            issuer: 'rvYAfWj5gh67oV6fW32ZzP3Aw4Eubs59B',
+            value: '0.5'
+          },
+          TakerPays: {
+            currency: 'USD',
+            issuer: 'rvYAfWj5gh67oV6fW32ZzP3Aw4Eubs59B',
+            value: '99.72233516476456'
+          },
+          index: 'A437D85DF80D250F79308F2B613CF5391C7CF8EE9099BC4E553942651CD9FA86',
+          owner_funds: '0.950363009783092',
+          is_fully_funded: false,
+          taker_gets_funded: '0.9484660776278363',
+          taker_pays_funded: '94.58325208561269'
+        }
   ]