diff --git a/InvenTree/InvenTree/metadata.py b/InvenTree/InvenTree/metadata.py
index c22b39dc43..6cf29ab945 100644
--- a/InvenTree/InvenTree/metadata.py
+++ b/InvenTree/InvenTree/metadata.py
@@ -32,6 +32,9 @@ class InvenTreeMetadata(SimpleMetadata):
 
     def determine_metadata(self, request, view):
         
+        self.request = request
+        self.view = view
+
         metadata = super().determine_metadata(request, view)
 
         user = request.user
@@ -136,6 +139,42 @@ class InvenTreeMetadata(SimpleMetadata):
         except AttributeError:
             pass
 
+        # Try to extract 'instance' information
+        instance = None
+
+        # Extract extra information if an instance is available
+        if hasattr(serializer, 'instance'):
+            instance = serializer.instance
+        
+        if instance is None:
+            try:
+                instance = self.view.get_object()
+            except:
+                pass
+
+        if instance is not None:
+            """
+            If there is an instance associated with this API View,
+            introspect that instance to find any specific API info.
+            """
+
+            if hasattr(instance, 'api_instance_filters'):
+
+                instance_filters = instance.api_instance_filters()
+
+                for field_name, field_filters in instance_filters.items():
+
+                    if field_name not in serializer_info.keys():
+                        # The field might be missing, but is added later on
+                        # This function seems to get called multiple times?
+                        continue
+
+                    if 'instance_filters' not in serializer_info[field_name].keys():
+                        serializer_info[field_name]['instance_filters'] = {}
+
+                    for key, value in field_filters.items():
+                        serializer_info[field_name]['instance_filters'][key] = value
+
         return serializer_info
 
     def get_field_info(self, field):
diff --git a/InvenTree/InvenTree/models.py b/InvenTree/InvenTree/models.py
index 2831a23151..3213838e78 100644
--- a/InvenTree/InvenTree/models.py
+++ b/InvenTree/InvenTree/models.py
@@ -93,6 +93,17 @@ class InvenTreeTree(MPTTModel):
         parent: The item immediately above this one. An item with a null parent is a top-level item
     """
 
+    def api_instance_filters(self):
+        """
+        Instance filters for InvenTreeTree models
+        """
+
+        return {
+            'parent': {
+                'exclude_tree': self.pk,
+            }
+        }
+
     def save(self, *args, **kwargs):
 
         try:
diff --git a/InvenTree/build/api.py b/InvenTree/build/api.py
index 47edb55545..eb6d42cc6d 100644
--- a/InvenTree/build/api.py
+++ b/InvenTree/build/api.py
@@ -104,6 +104,21 @@ class BuildList(generics.ListCreateAPIView):
 
         params = self.request.query_params
 
+        # exclude parent tree
+        exclude_tree = params.get('exclude_tree', None)
+
+        if exclude_tree is not None:
+
+            try:
+                build = Build.objects.get(pk=exclude_tree)
+
+                queryset = queryset.exclude(
+                    pk__in=[bld.pk for bld in build.get_descendants(include_self=True)]
+                )
+
+            except (ValueError, Build.DoesNotExist):
+                pass
+
         # Filter by "parent"
         parent = params.get('parent', None)
 
diff --git a/InvenTree/build/models.py b/InvenTree/build/models.py
index 5f8af9096b..084f9ab2db 100644
--- a/InvenTree/build/models.py
+++ b/InvenTree/build/models.py
@@ -96,6 +96,14 @@ class Build(MPTTModel):
     def get_api_url():
         return reverse('api-build-list')
 
+    def api_instance_filters(self):
+
+        return {
+            'parent': {
+                'exclude_tree': self.pk,
+            }
+        }
+
     def save(self, *args, **kwargs):
 
         try:
diff --git a/InvenTree/part/api.py b/InvenTree/part/api.py
index 39801070c7..28e5d4300a 100644
--- a/InvenTree/part/api.py
+++ b/InvenTree/part/api.py
@@ -105,6 +105,20 @@ class CategoryList(generics.ListCreateAPIView):
             except (ValueError, PartCategory.DoesNotExist):
                 pass
 
+        # Exclude PartCategory tree
+        exclude_tree = params.get('exclude_tree', None)
+
+        if exclude_tree is not None:
+            try:
+                cat = PartCategory.objects.get(pk=exclude_tree)
+
+                queryset = queryset.exclude(
+                    pk__in=[c.pk for c in cat.get_descendants(include_self=True)]
+                )
+
+            except (ValueError, PartCategory.DoesNotExist):
+                pass
+
         return queryset
 
     filter_backends = [
@@ -644,6 +658,20 @@ class PartList(generics.ListCreateAPIView):
             except (ValueError, Part.DoesNotExist):
                 pass
 
+        # Exclude part variant tree?
+        exclude_tree = params.get('exclude_tree', None)
+
+        if exclude_tree is not None:
+            try:
+                top_level_part = Part.objects.get(pk=exclude_tree)
+
+                queryset = queryset.exclude(
+                    pk__in=[prt.pk for prt in top_level_part.get_descendants(include_self=True)]
+                )
+
+            except (ValueError, Part.DoesNotExist):
+                pass
+
         # Filter by 'ancestor'?
         ancestor = params.get('ancestor', None)
 
diff --git a/InvenTree/part/models.py b/InvenTree/part/models.py
index 49be12e283..4cecd12f17 100644
--- a/InvenTree/part/models.py
+++ b/InvenTree/part/models.py
@@ -27,6 +27,7 @@ from markdownx.models import MarkdownxField
 from django_cleanup import cleanup
 
 from mptt.models import TreeForeignKey, MPTTModel
+from mptt.exceptions import InvalidMove
 from mptt.managers import TreeManager
 
 from stdimage.models import StdImageField
@@ -359,6 +360,17 @@ class Part(MPTTModel):
 
         return reverse('api-part-list')
 
+    def api_instance_filters(self):
+        """
+        Return API query filters for limiting field results against this instance
+        """
+
+        return {
+            'variant_of': {
+                'exclude_tree': self.pk,
+            }
+        }
+
     def get_context_data(self, request, **kwargs):
         """
         Return some useful context data about this part for template rendering
@@ -414,7 +426,12 @@ class Part(MPTTModel):
 
         self.full_clean()
 
-        super().save(*args, **kwargs)
+        try:
+            super().save(*args, **kwargs)
+        except InvalidMove:
+            raise ValidationError({
+                'variant_of': _('Invalid choice for parent part'),
+            })
 
         if add_category_templates:
             # Get part category
diff --git a/InvenTree/stock/api.py b/InvenTree/stock/api.py
index 56df35b5c3..cf58c7d4d9 100644
--- a/InvenTree/stock/api.py
+++ b/InvenTree/stock/api.py
@@ -343,6 +343,20 @@ class StockLocationList(generics.ListCreateAPIView):
             except (ValueError, StockLocation.DoesNotExist):
                 pass
 
+        # Exclude StockLocation tree
+        exclude_tree = params.get('exclude_tree', None)
+
+        if exclude_tree is not None:
+            try:
+                loc = StockLocation.objects.get(pk=exclude_tree)
+
+                queryset = queryset.exclude(
+                    pk__in=[subloc.pk for subloc in loc.get_descendants(include_self=True)]
+                )
+
+            except (ValueError, StockLocation.DoesNotExist):
+                pass
+
         return queryset
 
     filter_backends = [
@@ -719,6 +733,20 @@ class StockList(generics.ListCreateAPIView):
         if customer:
             queryset = queryset.filter(customer=customer)
 
+        # Exclude stock item tree
+        exclude_tree = params.get('exclude_tree', None)
+
+        if exclude_tree is not None:
+            try:
+                item = StockItem.objects.get(pk=exclude_tree)
+
+                queryset = queryset.exclude(
+                    pk__in=[it.pk for it in item.get_descendants(include_self=True)]
+                )
+
+            except (ValueError, StockItem.DoesNotExist):
+                pass
+
         # Filter by 'allocated' parts?
         allocated = params.get('allocated', None)
 
diff --git a/InvenTree/stock/models.py b/InvenTree/stock/models.py
index c2122f40ac..11d5de9bf1 100644
--- a/InvenTree/stock/models.py
+++ b/InvenTree/stock/models.py
@@ -191,6 +191,17 @@ class StockItem(MPTTModel):
     def get_api_url():
         return reverse('api-stock-list')
 
+    def api_instance_filters(self):
+        """
+        Custom API instance filters
+        """
+
+        return {
+            'parent': {
+                'exclude_tree': self.pk,
+            }
+        }
+
     # A Query filter which will be re-used in multiple places to determine if a StockItem is actually "in stock"
     IN_STOCK_FILTER = Q(
         quantity__gt=0,
diff --git a/InvenTree/templates/js/forms.js b/InvenTree/templates/js/forms.js
index 587ea07a16..4801ec77eb 100644
--- a/InvenTree/templates/js/forms.js
+++ b/InvenTree/templates/js/forms.js
@@ -350,6 +350,12 @@ function constructFormBody(fields, options) {
     for(field in fields) {
         fields[field].name = field;
 
+        
+        // If any "instance_filters" are defined for the endpoint, copy them across (overwrite)
+        if (fields[field].instance_filters) {
+            fields[field].filters = Object.assign(fields[field].filters || {}, fields[field].instance_filters);
+        }
+
         var field_options = displayed_fields[field];
 
         // Copy custom options across to the fields object