--- /dev/null
+var baseIteratee = require('./internal/baseIteratee'),
+ baseSortedIndexBy = require('./internal/baseSortedIndexBy');
+
+/**
+ * This method is like `_.sortedLastIndex` except that it accepts `iteratee`
+ * which is invoked for `value` and each element of `array` to compute their
+ * sort ranking. The iteratee is invoked with one argument: (value).
+ *
+ * @static
+ * @memberOf _
+ * @category Array
+ * @param {Array} array The sorted array to inspect.
+ * @param {*} value The value to evaluate.
+ * @param {Function|Object|string} [iteratee=_.identity] The iteratee invoked per element.
+ * @returns {number} Returns the index at which `value` should be inserted into `array`.
+ * @example
+ *
+ * // using the `_.property` iteratee shorthand
+ * _.sortedLastIndexBy([{ 'x': 4 }, { 'x': 5 }], { 'x': 4 }, 'x');
+ * // => 1
+ */
+function sortedLastIndexBy(array, value, iteratee) {
+ return baseSortedIndexBy(array, value, baseIteratee(iteratee), true);
+}
+
+module.exports = sortedLastIndexBy;