diff --git a/oml/changelog.py b/oml/changelog.py
index 562f609..7376600 100644
--- a/oml/changelog.py
+++ b/oml/changelog.py
@@ -160,25 +160,17 @@ class Changelog(db.Model):
             i.modified = ts2datetime(timestamp)
             if user not in i.users:
                 i.add_user(user)
-            i.info['_from'] = user.id
             i.update()
         return True
 
     def action_edititem(self, user, timestamp, itemid, meta):
         from user.models import Metadata
         m = Metadata.get_or_create(user.id, itemid)
-        m.edit(meta)
-        #FIXME: "sometimes" update item too...
+        m.edit(meta, modified=ts2datetime(timestamp))
         from item.models import Item
         i = Item.get(itemid)
         if i:
-            update = False
-            if len(i.users) == 1 and user in i.users:
-                update = True
-            if i.info.get('_from') == user.id:
-                update = True
-            if update:
-                i.edit(meta, ts2datetime(timestamp))
+            i.sync_metadata()
         return True
 
     def action_removeitem(self, user, timestamp, itemid):
diff --git a/oml/item/api.py b/oml/item/api.py
index 0b1edeb..f90a576 100644
--- a/oml/item/api.py
+++ b/oml/item/api.py
@@ -140,7 +140,7 @@ def edit(data):
     for id in ids:
         item = models.Item.get(id)
         if item and item.json()['mediastate'] == 'available':
-            item.edit(data, reset_from=True)
+            item.edit(data)
             response = item.json()
             edited.append(id)
         else:
diff --git a/oml/item/models.py b/oml/item/models.py
index 59f9b6c..6805c1b 100644
--- a/oml/item/models.py
+++ b/oml/item/models.py
@@ -3,6 +3,7 @@
 from datetime import datetime
 import base64
 import hashlib
+import json
 import os
 import re
 import shutil
@@ -10,6 +11,7 @@ import stat
 import unicodedata
 
 import ox
+from sqlalchemy.orm import load_only
 from sqlalchemy.schema import CreateTable
 import sqlalchemy as sa
 
@@ -136,7 +138,7 @@ class Item(db.Model):
             for k in list(j):
                 if k not in keys:
                     del j[k]
-        for key in [k['id'] for k in settings.config['itemKeys'] if isinstance(k['type'], list)]:
+        for key in self.array_keys:
             if key in j and not isinstance(j[key], list):
                 j[key] = [j[key]]
         return j
@@ -272,11 +274,12 @@ class Item(db.Model):
         'place',
         'publisher',
         'series',
+        'sharemetadata',
         'tableofcontents',
         'title'
     )
 
-    def update_meta(self, data, modified=None, reset_from=False):
+    def update_metadata(self, data, modified=None):
         update = False
         record = {}
         for key in self.meta_keys:
@@ -289,9 +292,6 @@ class Item(db.Model):
             if key not in self.meta_keys:
                 del self.meta[key]
                 update = True
-        if reset_from and '_from' in self.info:
-            del self.info['_from']
-            update = True
         if update:
             self.update(modified)
             self.save()
@@ -300,13 +300,58 @@ class Item(db.Model):
             user = state.user()
             if record and user in self.users:
                 Changelog.record_ts(user, modified, 'edititem', self.id, record)
+                logger.debug('edititem foobar, got sharemetadata?', record)
+                if 'sharemetadata' in record and not record['sharemetadata']:
+                    logger.debug('metadata no longer true, lets sync up')
+                    self.sync_metadata()
 
-    def edit(self, data, modified=None, reset_from=False):
+    def edit(self, data, modified=None):
         Scrape.query.filter_by(item_id=self.id).delete()
-        self.update_meta(data, modified, reset_from=reset_from)
+        self.update_metadata(data, modified)
         for f in self.files.all():
             f.move()
 
+    def get_hash(self):
+        return utils.get_meta_hash(self.meta.copy())
+
+    def sync_metadata(self):
+        from user.models import Metadata
+        if self.meta.get('sharemetadata'):
+            return
+        peers = [u for u in self.users if u.id != settings.USER_ID]
+        peers.sort(key=lambda u: ox.sort_string(str(u.info.get('index', ''))
+            + 'Z' + (u.info.get('name') or '')))
+        sync_from = None
+        first_peer = None
+        # get first peer with sharemetadata set
+        for u in peers:
+            m = Metadata.get(u.id, self.id)
+            if m:
+                if m.data.get('sharemetadata'):
+                    sync_from = m
+                    break
+                if not first_peer:
+                    first_peer = m
+        # of fall back to first peer that has this item
+        # in case its not available locally
+        if not sync_from and self.info['mediastate'] != 'available' and first_peer:
+            logger.debug('syncing from first peer that has item %s', first_peer)
+            sync_from = first_peer
+        if sync_from:
+            if self.get_hash() != sync_from.data_hash:
+                logger.debug('update %s with metadata from %s', self, sync_from.user_id)
+                record = {}
+                for key in sync_from.data:
+                    if key != 'sharemetadata' and self.meta.get(key) != sync_from.data[key]:
+                        record[key] = self.meta[key] = sync_from.data[key]
+                for key in set(self.meta)-set(sync_from.data):
+                    record[key] = self.meta[key] = [] if key in self.array_keys else ''
+                self.update(sync_from.modified)
+                self.save()
+                user = state.user()
+                if record and user in self.users:
+                    Changelog.record_ts(user, self.modified, 'edititem', self.id, record)
+
     def extract_preview(self):
         path = self.get_path()
         if path:
@@ -493,6 +538,7 @@ for key in config['itemKeys']:
 Item.id_keys = ['isbn', 'lccn', 'olid', 'oclc', 'asin']
 Item.item_keys = config['itemKeys'] 
 Item.filter_keys = [k['id'] for k in config['itemKeys'] if k.get('filter')]
+Item.array_keys = [k['id'] for k in config['itemKeys'] if isinstance(k['type'], list)]
 
 class Find(db.Model):
     __tablename__ = 'find'
@@ -814,3 +860,25 @@ def update_sort_table():
             for q in sql:
                 s.connection().execute(q)
             s.commit()
+
+
+def sync_metadata(ids=None):
+    #logger.debug('sync_metadata(%s)', len(ids) if ids else ids)
+    step = 1000
+    delay = 10
+    with db.session():
+        if not ids:
+            ids = [i.id for i in Item.query.options(load_only('id'))]
+        if len(ids) > step:
+            later = ids[step:]
+            ids = ids[:step]
+        else:
+            later = []
+        if ids:
+            for i in Item.query.filter(Item.id.in_(ids)):
+                i.sync_metadata()
+        if later:
+            if state.main and state.tasks:
+                state.main.call_later(delay, lambda: state.tasks.queue('syncmetadata', [later]))
+        #else:
+        #    logger.debug('sync_metadata done')
diff --git a/oml/settings.py b/oml/settings.py
index 23ac3e9..fefb4d0 100644
--- a/oml/settings.py
+++ b/oml/settings.py
@@ -101,4 +101,4 @@ USER_AGENT = 'OpenMediaLibrary/%s' % VERSION
 
 DEBUG_HTTP = server.get('debug_http', False)
 
-DB_VERSION = 4
+DB_VERSION = 5
diff --git a/oml/setup.py b/oml/setup.py
index 0bbd7fa..7c47d78 100644
--- a/oml/setup.py
+++ b/oml/setup.py
@@ -477,7 +477,7 @@ def update_database():
         'CREATE INDEX ix_user_metadata_data_hash ON user_metadata (data_hash)',
         'CREATE UNIQUE INDEX listitem_index on listitem(list_id, item_id)',
         'CREATE UNIQUE INDEX useritem_index on useritem(user_id, item_id)',
-        'CREATE UNIQUE INDEX user_metadata_index ON user_metadata(id, user_id)',
+        'CREATE UNIQUE INDEX user_metadata_index ON user_metadata(item_id, user_id)',
     ]
     layout = db.get_layout()
     sql = []
diff --git a/oml/tasks.py b/oml/tasks.py
index 37d82c3..430ea19 100644
--- a/oml/tasks.py
+++ b/oml/tasks.py
@@ -22,6 +22,7 @@ class Tasks(Thread):
 
     def run(self):
         import item.scan
+        from item.models import sync_metadata
         from user.models import export_list, update_user_peering
         while self.connected:
             m = self.q.get()
@@ -40,6 +41,10 @@ class Tasks(Thread):
                         item.scan.import_folder()
                     elif action == 'peering':
                         update_user_peering(*data)
+                    elif action == 'syncmetadata':
+                        if not data:
+                            data = []
+                        sync_metadata(*data)
                     else:
                         trigger_event('error', {'error': 'unknown action'})
                 except:
diff --git a/oml/update.py b/oml/update.py
index 8cf0878..d6e5bd9 100644
--- a/oml/update.py
+++ b/oml/update.py
@@ -303,6 +303,8 @@ class Update(Thread):
                 db_version = migrate_3()
             if db_version < 4:
                 db_version = migrate_4()
+            if db_version < 5:
+                db_version = migrate_5()
             settings.server['db_version'] = settings.DB_VERSION
 
     def run(self):
@@ -383,3 +385,29 @@ def migrate_4():
                 session.add(i)
         session.commit()
     return 4
+
+def migrate_5():
+    db.run_sql([
+        'DROP INDEX IF EXISTS user_metadata_index',
+        'CREATE UNIQUE INDEX user_metadata_index ON user_metadata(item_id, user_id)'
+    ]),
+    with db.session() as session:
+        import user.models
+        for m in user.models.Metadata.query:
+            data_hash = m.get_hash()
+            if m.data_hash != data_hash:
+                m.data_hash = data_hash
+                session.add(m)
+        session.commit()
+        import item.models
+        for i in item.models.Item.query:
+            update = False
+            if '_from' in i.info:
+                del i.info['_from']
+                update = True
+            if update:
+                session.add(i)
+        session.commit()
+        for i in item.models.Item.query:
+            i.sync_metadata()
+    return 5
diff --git a/oml/user/api.py b/oml/user/api.py
index 84a0967..70bf985 100644
--- a/oml/user/api.py
+++ b/oml/user/api.py
@@ -314,6 +314,8 @@ def sortUsers(data):
         n += 1
         state.db.session.add(u)
     state.db.session.commit()
+    if state.tasks:
+        state.tasks.queue('syncmetadata')
     return {}
 actions.register(sortUsers, cache=False)
 
diff --git a/oml/user/models.py b/oml/user/models.py
index 7dd284c..af88441 100644
--- a/oml/user/models.py
+++ b/oml/user/models.py
@@ -380,7 +380,7 @@ class Metadata(db.Model):
 
     @classmethod
     def get(cls, user_id, item_id):
-        return cls.query.filter_by(user_id=user_id,item_id=item_id).first()
+        return cls.query.filter_by(item_id=item_id, user_id=user_id).first()
 
     @classmethod
     def get_or_create(cls, user_id, item_id, data=None, commit=True):
@@ -392,19 +392,24 @@ class Metadata(db.Model):
                 m.data = data
             else:
                 m.data = {}
-            m.save(commit)
+            m.save(commit=commit)
         elif data:
-            m.edit(data, commit)
+            m.edit(data, commit=commit)
         return m
 
-    def save(self, commit=True):
-        self.modified = datetime.utcnow()
-        self.data_hash = hashlib.sha1(json.dumps(self.data, ensure_ascii=False, sort_keys=True).encode()).hexdigest()
+    def get_hash(self):
+        return utils.get_meta_hash(self.data.copy())
+
+    def save(self, commit=True, modified=None):
+        if modified is None:
+            self.modified = datetime.utcnow()
+        else:
+            self.modified = modified
         state.db.session.add(self)
         if commit:
             state.db.session.commit()
 
-    def edit(self, data, commit=True):
+    def edit(self, data, commit=True, modified=True):
         changes = {}
         if 'isbn' in data and isinstance(data['isbn'], list):
             isbns = [utils.to_isbn13(isbn) for isbn in data['isbn']]
@@ -420,7 +425,8 @@ class Metadata(db.Model):
                 self.data[key] = data[key]
                 changes[key] = data[key]
         if changes:
-            self.save(commit)
+            self.data_hash = self.get_hash()
+            self.save(commit=commit, modified=modified)
         return changes
 
     def delete(self):
diff --git a/oml/utils.py b/oml/utils.py
index 71ee624..110b207 100644
--- a/oml/utils.py
+++ b/oml/utils.py
@@ -2,18 +2,19 @@
 # vi:si:et:sw=4:sts=4:ts=4
 
 
-import os
-import sys
-from PIL import Image
-from io import StringIO, BytesIO
-import re
-import stdnum.isbn
-import socket
-import time
-import hashlib
 from datetime import datetime
-import subprocess
+from io import StringIO, BytesIO
+from PIL import Image
 import base64
+import hashlib
+import json
+import os
+import re
+import socket
+import stdnum.isbn
+import subprocess
+import sys
+import time
 
 import ox
 from OpenSSL.crypto import (
@@ -391,3 +392,13 @@ def get_ratio(data):
         return img.size[0]/img.size[1]
     except:
         return 1
+
+
+def get_meta_hash(data):
+    if 'sharemetadata' in data:
+        del data['sharemetadata']
+    for key in list(data):
+        if not data[key]:
+            del data[key]
+    return hashlib.sha1(json.dumps(data,
+        ensure_ascii=False, sort_keys=True).encode()).hexdigest()
diff --git a/static/js/infoView.js b/static/js/infoView.js
index 2e39e2b..d845649 100644
--- a/static/js/infoView.js
+++ b/static/js/infoView.js
@@ -295,17 +295,24 @@ oml.ui.infoView = function(externalData, isMixed) {
         return $element;
     }
 
-    function renderShareButton() {
+    function renderShareButton(data) {
         return Ox.Checkbox({
                 style: 'squared',
                 title: Ox._('Share Metadata'),
-                value: false,
+                value: data.sharemetadata,
                 width: 128,
             })
             .css({marginTop: '8px'})
             .bindEvent({
-                change: function(data) {
-                    // ...
+                change: function(changeData) {
+                    oml.api.edit({
+                        id: data.id,
+                        sharemetadata: changeData.value
+                    }, function(result) {
+                        if (!changeData.value) {
+                            that.updateElement(result.data, [$icon, $info, $data]);
+                        }
+                    });
                 }
             });
     }
@@ -764,7 +771,7 @@ oml.ui.infoView = function(externalData, isMixed) {
                     });
 
                     if (data.mediastate == 'available') {
-                        renderShareButton().appendTo($data);
+                        renderShareButton(data).appendTo($data);
                     }
 
                     $('<div>').css({height: '16px'}).appendTo($data);