diff --git a/dist/lodash.compat.js b/dist/lodash.compat.js
index e16296fc1..94a84565f 100644
--- a/dist/lodash.compat.js
+++ b/dist/lodash.compat.js
@@ -1112,7 +1112,8 @@
       while (++index < length) {
         var value = array[index];
 
-        if (value && typeof value == 'object' && value.length && (isArray(value) || isArguments(value))) {
+        if (value && typeof value == 'object' && typeof value.length == 'number'
+            && (isArray(value) || isArguments(value))) {
           // recursively flatten arrays (susceptible to call stack limits)
           if (!isShallow) {
             value = baseFlatten(value, isShallow, isArgArrays);
diff --git a/dist/lodash.compat.min.js b/dist/lodash.compat.min.js
index 758e8e6c4..0d1c53ab7 100644
--- a/dist/lodash.compat.min.js
+++ b/dist/lodash.compat.min.js
@@ -8,7 +8,7 @@
 }function f(n){return typeof n.toString!="function"&&typeof(n+"")=="string"}function c(){}function p(n){n.length=0,y.length<j&&y.push(n)}function s(n){var t=n.k;t&&s(t),n.b=n.k=n.l=n.object=n.number=n.string=n.n=null,m.length<j&&m.push(n)}function g(n,t,e){t||(t=0),typeof e=="undefined"&&(e=n?n.length:0);var r=-1;e=e-t||0;for(var u=Array(0>e?0:e);++r<e;)u[r]=n[t+r];return u}function h(e){function y(n){return n&&typeof n=="object"&&!qe(n)&&ve.call(n,"__wrapped__")?n:new m(n)}function m(n,t){this.__chain__=!!t,this.__wrapped__=n
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diff --git a/dist/lodash.js b/dist/lodash.js
index 6e9e684ce..84d650bbd 100644
--- a/dist/lodash.js
+++ b/dist/lodash.js
@@ -843,7 +843,8 @@
       while (++index < length) {
         var value = array[index];
 
-        if (value && typeof value == 'object' && value.length && (isArray(value) || isArguments(value))) {
+        if (value && typeof value == 'object' && typeof value.length == 'number'
+            && (isArray(value) || isArguments(value))) {
           // recursively flatten arrays (susceptible to call stack limits)
           if (!isShallow) {
             value = baseFlatten(value, isShallow, isArgArrays);
diff --git a/dist/lodash.min.js b/dist/lodash.min.js
index a53527fb6..315de519d 100644
--- a/dist/lodash.min.js
+++ b/dist/lodash.min.js
@@ -10,8 +10,8 @@ for(var r=-1,u=M[typeof n]&&qe(n),o=u?u.length:0;++r<o&&(e=u[r],false!==t(n[e],e
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diff --git a/dist/lodash.underscore.js b/dist/lodash.underscore.js
index c49e6d656..fd745e06d 100644
--- a/dist/lodash.underscore.js
+++ b/dist/lodash.underscore.js
@@ -419,7 +419,8 @@
     while (++index < length) {
       var value = array[index];
 
-      if (value && typeof value == 'object' && value.length && (isArray(value) || isArguments(value))) {
+      if (value && typeof value == 'object' && typeof value.length == 'number'
+          && (isArray(value) || isArguments(value))) {
         // recursively flatten arrays (susceptible to call stack limits)
         if (!isShallow) {
           value = baseFlatten(value, isShallow, isArgArrays);
diff --git a/dist/lodash.underscore.min.js b/dist/lodash.underscore.min.js
index ba83d663b..a6c2e652e 100644
--- a/dist/lodash.underscore.min.js
+++ b/dist/lodash.underscore.min.js
@@ -4,7 +4,7 @@
  * Build: `lodash underscore exports="amd,commonjs,global,node" -o ./dist/lodash.underscore.js`
  */
 ;(function(){function n(n,r,t){t=(t||0)-1;for(var e=n?n.length:0;++t<e;)if(n[t]===r)return t;return-1}function r(n,r){var t=n.l,e=r.l;if(t!==e){if(t>e||typeof t=="undefined")return 1;if(t<e||typeof e=="undefined")return-1}return n.m-r.m}function t(n){return"\\"+vr[n]}function e(){}function u(n){return n instanceof u?n:new o(n)}function o(n,r){this.__chain__=!!r,this.__wrapped__=n}function i(n,r,t){if(typeof n!="function")return Q;if(typeof r=="undefined")return n;switch(t){case 1:return function(t){return n.call(r,t)
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 if(null==n||null==r)return n===r;var o=Or.call(n),i=Or.call(r);if(o!=i)return!1;switch(o){case fr:case ar:return+n==+r;case lr:return n!=+n?r!=+r:0==n?1/n==1/r:n==+r;case pr:case sr:return n==r+""}if(i=o==ir,!i){if(Ar.call(n,"__wrapped__")||r instanceof u)return a(n.__wrapped__||n,r.__wrapped__||r,t,e);if(o!=cr)return!1;var o=n.constructor,f=r.constructor;if(o!=f&&!(j(o)&&o instanceof o&&j(f)&&f instanceof f))return!1}for(t||(t=[]),e||(e=[]),o=t.length;o--;)if(t[o]==n)return e[o]==r;var l=!0,c=0;
 if(t.push(n),e.push(r),i){if(c=r.length,l=c==n.length)for(;c--&&(l=a(n[c],r[c],t,e)););return l}return Lr(r,function(r,u,o){return Ar.call(o,u)?(c++,!(l=Ar.call(n,u)&&a(n[u],r,t,e))&&rr):void 0}),l&&Lr(n,function(n,r,t){return Ar.call(t,r)?!(l=-1<--c)&&rr:void 0}),l}function l(n,r,t){for(var e=-1,u=v(),o=n?n.length:0,i=[],f=t?[]:i;++e<o;){var a=n[e],l=t?t(a,e,n):a;(r?!e||f[f.length-1]!==l:0>u(f,l))&&(t&&f.push(l),i.push(a))}return i}function c(n){return function(r,t,e){var u={};t=K(t,e,3),e=-1;var o=r?r.length:0;
 if(typeof o=="number")for(;++e<o;){var i=r[e];n(u,i,t(i,e,r),r)}else Qr(r,function(r,e,o){n(u,r,t(r,e,o),o)});return u}}function p(n,r,t,e,u,o){var i=1&r,f=2&r,a=4&r,l=8&r,c=16&r,h=32&r,v=n;if(!f&&!j(n))throw new TypeError;if(c&&!t.length&&(r&=-17,c=t=!1),h&&!e.length&&(r&=-33,h=e=!1),!i||f||a||h||!(Cr.fastBind||Br&&c))y=function(){var g=arguments,m=i?u:this;return(a||c||h)&&(g=Ir.call(g),c&&Sr.apply(g,t),h&&Tr.apply(g,e),a&&g.length<o)?(r|=16,p(n,l?r:-4&r,g,null,u,o)):(f&&(n=m[v]),this instanceof y?(m=s(n.prototype),g=n.apply(m,g),x(g)?g:m):n.apply(m,g))
diff --git a/lodash.js b/lodash.js
index becd50a7c..4c3753eea 100644
--- a/lodash.js
+++ b/lodash.js
@@ -1131,7 +1131,8 @@
       while (++index < length) {
         var value = array[index];
 
-        if (value && typeof value == 'object' && value.length && (isArray(value) || isArguments(value))) {
+        if (value && typeof value == 'object' && typeof value.length == 'number'
+            && (isArray(value) || isArguments(value))) {
           // recursively flatten arrays (susceptible to call stack limits)
           if (!isShallow) {
             value = baseFlatten(value, isShallow, isArgArrays);
diff --git a/test/test.js b/test/test.js
index 41ec36045..ab7488c99 100644
--- a/test/test.js
+++ b/test/test.js
@@ -1336,6 +1336,11 @@
         ok(pass);
       }
     });
+
+    test('should work with empty arrays', function() {
+      var actual = _.flatten([[], [[]], [[], [[[]]]]]);
+      deepEqual(actual, []);
+    });
   }(1, 2, 3));
 
   /*--------------------------------------------------------------------------*/