Index: __init__.py
===================================================================

--- ./modules/stock_lot/__init__.py
+++ ./modules/stock_lot/__init__.py
@@ -21,4 +21,9 @@
         Template,
         Product,
         TemplateLotType,
+        Location,
+        LotByLocationStart,
         module='stock_lot', type_='model')
+    Pool.register(
+        LotByLocation,
+        module='stock_lot', type_='wizard')

Index: stock.py
===================================================================

--- ./modules/stock_lot/stock.py
+++ ./modules/stock_lot/stock.py
@@ -1,17 +1,20 @@
 #This file is part of Tryton.  The COPYRIGHT file at the top level of
 #this repository contains the full copyright notices and license terms.
+import datetime
 from collections import defaultdict
 
 from trytond.model import ModelView, ModelSQL, Workflow, fields
-from trytond.pyson import Eval
+from trytond.pyson import PYSONEncoder, Eval
 from trytond.pool import Pool, PoolMeta
 from trytond.transaction import Transaction
+from trytond.wizard import Wizard, StateView, StateAction, Button
 from trytond.modules.stock import StockMixin
 
 __all__ = ['Lot', 'LotType', 'Move', 'ShipmentIn', 'ShipmentOut',
     'ShipmentOutReturn',
     'Period', 'PeriodCacheLot',
-    'Inventory', 'InventoryLine']
+    'Inventory', 'InventoryLine',
+    'Location', 'LotByLocation', 'LotByLocationStart']
 __metaclass__ = PoolMeta
 
 
@@ -294,3 +297,73 @@
         if move:
             move.lot = self.lot
         return move
+
+
+class Location:
+    __name__ = 'stock.location'
+
+    @classmethod
+    def _quantity_grouping_and_key(cls):
+        if Transaction().context.get('lot'):
+            lot_id = Transaction().context['lot']
+            product_id = Transaction().context['product']
+            return ('product', 'lot'), (product_id, lot_id)
+        return super(Location, cls)._quantity_grouping_and_key()
+
+
+class LotByLocationStart(ModelView):
+    'Lot by Location'
+    __name__ = 'stock.lot.by_location.start'
+    forecast_date = fields.Date(
+        'At Date', help=('Allow to compute expected '
+            'stock quantities for this date.\n'
+            '* An empty value is an infinite date in the future.\n'
+            '* A date in the past will provide historical values.'))
+
+    @staticmethod
+    def default_forecast_date():
+        Date = Pool().get('ir.date')
+        return Date.today()
+
+
+class LotByLocation(Wizard):
+    'Lot by Location'
+    __name__ = 'stock.lot.by_location'
+    start = StateView('stock.lot.by_location.start',
+        'stock_lot.lot_by_location_start_view_form', [
+            Button('Cancel', 'end', 'tryton-cancel'),
+            Button('Open', 'open', 'tryton-ok', default=True),
+            ])
+    open = StateAction('stock.act_location_quantity_tree')
+
+    def do_open(self, action):
+        pool = Pool()
+        Lot = pool.get('stock.lot')
+        Lang = pool.get('ir.lang')
+
+        context = {}
+        lot_id = Transaction().context['active_id']
+        context['lot'] = lot_id
+
+        lot = Lot(lot_id)
+        context['product'] = lot.product.id
+
+        if self.start.forecast_date:
+            context['stock_date_end'] = self.start.forecast_date
+        else:
+            context['stock_date_end'] = datetime.date.max
+        action['pyson_context'] = PYSONEncoder().encode(context)
+
+        for code in [Transaction().language, 'en_US']:
+            langs = Lang.search([
+                    ('code', '=', code),
+                    ])
+            if langs:
+                break
+        lang, = langs
+        date = Lang.strftime(context['stock_date_end'],
+            lang.code, lang.date)
+
+        action['name'] += ' - %s (%s) @ %s' % (lot.rec_name,
+            lot.product.default_uom.rec_name, date)
+        return action, {}

Index: stock.xml
===================================================================

--- ./modules/stock_lot/stock.xml
+++ ./modules/stock_lot/stock.xml
@@ -48,6 +48,28 @@
             <field name="perm_delete" eval="True"/>
         </record>
 
+        <record model="ir.action.wizard" id="wizard_lot_by_location">
+            <field name="name">Lot by Locations</field>
+            <field name="wiz_name">stock.lot.by_location</field>
+            <field name="model">stock.lot</field>
+        </record>
+        <record model="ir.action.keyword" id="act_location_quantity_keyword1">
+            <field name="keyword">form_relate</field>
+            <field name="model">stock.lot,-1</field>
+            <field name="action" ref="wizard_lot_by_location"/>
+        </record>
+        <record model="ir.action-res.group"
+            id="wizard_lot_by_location-group_stock">
+            <field name="action" ref="wizard_lot_by_location"/>
+            <field name="group" ref="stock.group_stock"/>
+        </record>
+
+        <record model="ir.ui.view" id="lot_by_location_start_view_form">
+            <field name="model">stock.lot.by_location.start</field>
+            <field name="type">form</field>
+            <field name="name">lot_by_location_start_form</field>
+        </record>
+
         <record model="stock.lot.type" id="type_supplier">
             <field name="code">supplier</field>
             <field name="name">Supplier</field>

Index: view/lot_by_location_start_form.xml
===================================================================
new file mode 100644

--- /dev/null
+++ ./modules/stock_lot/view/lot_by_location_start_form.xml
@@ -0,0 +1,7 @@
+<?xml version="1.0"?>
+<!-- This file is part of Tryton.  The COPYRIGHT file at the top level of
+this repository contains the full copyright notices and license terms. -->
+<form string="Lot by Location">
+    <label name="forecast_date"/>
+    <field name="forecast_date"/>
+</form>