diff --git a/.rubocop_styleguide.yml b/.rubocop_styleguide.yml
index a6a2fab4f4..5459d63ebc 100644
--- a/.rubocop_styleguide.yml
+++ b/.rubocop_styleguide.yml
@@ -39,6 +39,7 @@ Metrics/BlockLength:
     "put",
     "resource",
     "resources",
+    "response",
     "scenario",
     "shared_examples",
     "shared_examples_for",
diff --git a/app/models/spree/product.rb b/app/models/spree/product.rb
index e7bf67a3d3..be905c8ccc 100755
--- a/app/models/spree/product.rb
+++ b/app/models/spree/product.rb
@@ -272,18 +272,6 @@ module Spree
       end
     end
 
-    private
-
-    def update_units
-      return unless saved_change_to_variant_unit? || saved_change_to_variant_unit_name?
-
-      variants.each(&:update_units)
-    end
-
-    def touch_distributors
-      Enterprise.distributing_products(id).each(&:touch)
-    end
-
     def ensure_standard_variant
       return unless variants.empty?
 
@@ -298,6 +286,18 @@ module Spree
       variants << variant
     end
 
+    private
+
+    def update_units
+      return unless saved_change_to_variant_unit? || saved_change_to_variant_unit_name?
+
+      variants.each(&:update_units)
+    end
+
+    def touch_distributors
+      Enterprise.distributing_products(id).each(&:touch)
+    end
+
     def validate_image
       return if image.blank? || image.valid?
 
diff --git a/engines/dfc_provider/app/controllers/dfc_provider/supplied_products_controller.rb b/engines/dfc_provider/app/controllers/dfc_provider/supplied_products_controller.rb
index e4daf3155f..21b4c4b59d 100644
--- a/engines/dfc_provider/app/controllers/dfc_provider/supplied_products_controller.rb
+++ b/engines/dfc_provider/app/controllers/dfc_provider/supplied_products_controller.rb
@@ -14,13 +14,19 @@ module DfcProvider
 
       return head :bad_request unless supplied_product
 
-      product = SuppliedProductBuilder.import(supplied_product)
-      product.supplier = current_enterprise
-      product.save!
+      variant = SuppliedProductBuilder.import_variant(supplied_product)
+      product = variant.product
 
-      supplied_product = SuppliedProductBuilder.supplied_product(
-        product.variants.first
-      )
+      if product.new_record?
+        product.supplier = current_enterprise
+        product.save!
+      end
+
+      if variant.new_record?
+        variant.save!
+      end
+
+      supplied_product = SuppliedProductBuilder.supplied_product(variant)
       render json: DfcIo.export(supplied_product)
     end
 
diff --git a/engines/dfc_provider/app/services/dfc_io.rb b/engines/dfc_provider/app/services/dfc_io.rb
index 2457eb4a46..99bf63df66 100644
--- a/engines/dfc_provider/app/services/dfc_io.rb
+++ b/engines/dfc_provider/app/services/dfc_io.rb
@@ -1,8 +1,5 @@
 # frozen_string_literal: true
 
-# Load our monkey-patches:
-require "data_food_consortium/connector/connector"
-
 # Our interface to the DFC Connector library.
 module DfcIo
   # Serialise DFC Connector subjects as JSON-LD string.
diff --git a/engines/dfc_provider/app/services/dfc_loader.rb b/engines/dfc_provider/app/services/dfc_loader.rb
index d9ef128c96..1fae62f9f4 100644
--- a/engines/dfc_provider/app/services/dfc_loader.rb
+++ b/engines/dfc_provider/app/services/dfc_loader.rb
@@ -1,7 +1,5 @@
 # frozen_string_literal: true
 
-require "data_food_consortium/connector/connector"
-
 class DfcLoader
   def self.connector
     @connector ||= load_vocabularies
diff --git a/engines/dfc_provider/app/services/supplied_product_builder.rb b/engines/dfc_provider/app/services/supplied_product_builder.rb
index fe036dcfb1..a706a72eb7 100644
--- a/engines/dfc_provider/app/services/supplied_product_builder.rb
+++ b/engines/dfc_provider/app/services/supplied_product_builder.rb
@@ -7,16 +7,35 @@ class SuppliedProductBuilder < DfcBuilder
       id: variant.id,
     )
 
-    DataFoodConsortium::Connector::SuppliedProduct.new(
+    DfcProvider::SuppliedProduct.new(
       id,
       name: variant.name_to_display,
       description: variant.description,
       productType: product_type,
       quantity: QuantitativeValueBuilder.quantity(variant),
+      spree_product_id: variant.product.id,
     )
   end
 
-  def self.import(supplied_product)
+  def self.import_variant(supplied_product)
+    product_id = supplied_product.spree_product_id
+
+    if product_id.present?
+      product = Spree::Product.find(product_id)
+      Spree::Variant.new(
+        product:,
+        price: 0,
+      ).tap do |variant|
+        apply(supplied_product, variant)
+      end
+    else
+      product = import_product(supplied_product)
+      product.ensure_standard_variant
+      product.variants.first
+    end
+  end
+
+  def self.import_product(supplied_product)
     Spree::Product.new(
       name: supplied_product.name,
       description: supplied_product.description,
diff --git a/engines/dfc_provider/lib/data_food_consortium/connector/importer.rb b/engines/dfc_provider/lib/data_food_consortium/connector/importer.rb
index e46a021d73..b8365cdc8a 100644
--- a/engines/dfc_provider/lib/data_food_consortium/connector/importer.rb
+++ b/engines/dfc_provider/lib/data_food_consortium/connector/importer.rb
@@ -15,21 +15,28 @@ module DataFoodConsortium
       ].freeze
 
       def self.type_map
-        @type_map ||= TYPES.each_with_object({}) do |clazz, result|
-          # Methods with variable arguments have a negative arity of -n-1
-          # where n is the number of required arguments.
-          number_of_required_args = -1 * (clazz.instance_method(:initialize).arity + 1)
-          args = Array.new(number_of_required_args)
-          type_uri = clazz.new(*args).semanticType
-          result[type_uri] = clazz
-
-          # Add support for the old DFC v1.7 URLs:
-          new_type_uri = type_uri.gsub(
-            "https://github.com/datafoodconsortium/ontology/releases/latest/download/DFC_BusinessOntology.owl#",
-            "http://static.datafoodconsortium.org/ontologies/DFC_BusinessOntology.owl#"
-          )
-          result[new_type_uri] = clazz
+        unless @type_map
+          @type_map = {}
+          TYPES.each(&method(:register_type))
         end
+
+        @type_map
+      end
+
+      def self.register_type(clazz)
+        # Methods with variable arguments have a negative arity of -n-1
+        # where n is the number of required arguments.
+        number_of_required_args = -1 * (clazz.instance_method(:initialize).arity + 1)
+        args = Array.new(number_of_required_args)
+        type_uri = clazz.new(*args).semanticType
+        type_map[type_uri] = clazz
+
+        # Add support for the old DFC v1.7 URLs:
+        new_type_uri = type_uri.gsub(
+          "https://github.com/datafoodconsortium/ontology/releases/latest/download/DFC_BusinessOntology.owl#",
+          "http://static.datafoodconsortium.org/ontologies/DFC_BusinessOntology.owl#"
+        )
+        type_map[new_type_uri] = clazz
       end
 
       def import(json_string_or_io)
@@ -120,11 +127,12 @@ module DataFoodConsortium
       end
 
       def guess_setter_name(predicate)
-        fragment = predicate.fragment
-
-        # Some predicates are named like `hasQuantity`
-        # but the attribute name would be `quantity`.
-        name = fragment.sub(/^has/, "").camelize(:lower)
+        name =
+          # Some predicates are named like `hasQuantity`
+          # but the attribute name would be `quantity`.
+          predicate.fragment&.sub(/^has/, "")&.camelize(:lower) ||
+          # And sometimes the URI looks like `ofn:spree_product_id`.
+          predicate.to_s.split(":").last
 
         "#{name}="
       end
diff --git a/engines/dfc_provider/lib/dfc_provider.rb b/engines/dfc_provider/lib/dfc_provider.rb
index b0cf98121a..4676736439 100644
--- a/engines/dfc_provider/lib/dfc_provider.rb
+++ b/engines/dfc_provider/lib/dfc_provider.rb
@@ -1,6 +1,14 @@
 # frozen_string_literal: true
 
+# Load our monkey-patches of the DFC Connector:
+require "data_food_consortium/connector/connector"
+
+# Our Rails engine
 require "dfc_provider/engine"
 
+# Custom data types
+require "dfc_provider/supplied_product"
+
 module DfcProvider
+  DataFoodConsortium::Connector::Importer.register_type(SuppliedProduct)
 end
diff --git a/engines/dfc_provider/lib/dfc_provider/supplied_product.rb b/engines/dfc_provider/lib/dfc_provider/supplied_product.rb
new file mode 100644
index 0000000000..06b762ba87
--- /dev/null
+++ b/engines/dfc_provider/lib/dfc_provider/supplied_product.rb
@@ -0,0 +1,17 @@
+# frozen_string_literal: true
+
+module DfcProvider
+  class SuppliedProduct < DataFoodConsortium::Connector::SuppliedProduct
+    attr_accessor :spree_product_id
+
+    def initialize(semantic_id, spree_product_id: nil, **properties)
+      super(semantic_id, **properties)
+
+      self.spree_product_id = spree_product_id
+
+      registerSemanticProperty("ofn:spree_product_id") do
+        self.spree_product_id
+      end
+    end
+  end
+end
diff --git a/engines/dfc_provider/spec/lib/data_food_consortium/connector/connector_spec.rb b/engines/dfc_provider/spec/lib/data_food_consortium/connector/connector_spec.rb
index 48d7cbd3e6..f0bda34bf9 100644
--- a/engines/dfc_provider/spec/lib/data_food_consortium/connector/connector_spec.rb
+++ b/engines/dfc_provider/spec/lib/data_food_consortium/connector/connector_spec.rb
@@ -21,7 +21,7 @@ describe DataFoodConsortium::Connector::Connector, vcr: true do
   it "imports" do
     json = connector.export(product)
     result = connector.import(json)
-    expect(result.class).to eq product.class
+    expect(result).to be_a product.class
     expect(result.semanticType).to eq product.semanticType
     expect(result.semanticId).to eq "https://example.net/tomato"
     expect(result.name).to eq "Tomato"
@@ -32,7 +32,7 @@ describe DataFoodConsortium::Connector::Connector, vcr: true do
     io = StringIO.new(json)
     result = connector.import(io)
 
-    expect(result.class).to eq product.class
+    expect(result).to be_a product.class
     expect(result.semanticType).to eq product.semanticType
     expect(result.semanticId).to eq "https://example.net/tomato"
     expect(result.name).to eq "Tomato"
diff --git a/engines/dfc_provider/spec/lib/data_food_consortium/connector/importer_spec.rb b/engines/dfc_provider/spec/lib/data_food_consortium/connector/importer_spec.rb
index e64dce16a7..04e9407ce6 100644
--- a/engines/dfc_provider/spec/lib/data_food_consortium/connector/importer_spec.rb
+++ b/engines/dfc_provider/spec/lib/data_food_consortium/connector/importer_spec.rb
@@ -100,7 +100,7 @@ describe DataFoodConsortium::Connector::Importer do
   it "imports a single object with simple properties" do
     result = import(product)
 
-    expect(result.class).to eq product.class
+    expect(result).to be_a product.class
     expect(result.semanticType).to eq product.semanticType
     expect(result.semanticId).to eq "https://example.net/tomato"
     expect(result.name).to eq "Tomato"
@@ -111,7 +111,7 @@ describe DataFoodConsortium::Connector::Importer do
   it "imports an object with referenced context" do
     result = connector.import(product_data)
 
-    expect(result.class).to eq DataFoodConsortium::Connector::SuppliedProduct
+    expect(result).to be_a DataFoodConsortium::Connector::SuppliedProduct
     expect(result.semanticType).to eq "https://github.com/datafoodconsortium/ontology/releases/latest/download/DFC_BusinessOntology.owl#SuppliedProduct"
     expect(result.semanticId).to eq "https://example.net/tomato"
     expect(result.name).to eq "Tomato"
@@ -122,7 +122,7 @@ describe DataFoodConsortium::Connector::Importer do
   it "imports an object with included context" do
     result = connector.import(product_data_with_context)
 
-    expect(result.class).to eq DataFoodConsortium::Connector::SuppliedProduct
+    expect(result).to be_a DataFoodConsortium::Connector::SuppliedProduct
     expect(result.semanticType).to eq "https://github.com/datafoodconsortium/ontology/releases/latest/download/DFC_BusinessOntology.owl#SuppliedProduct"
     expect(result.semanticId).to eq "https://example.net/tomato"
     expect(result.name).to eq "Tomato"
@@ -133,7 +133,7 @@ describe DataFoodConsortium::Connector::Importer do
   it "imports an object with DFC v1.8 context" do
     result = connector.import(product_data_with_context_v1_8)
 
-    expect(result.class).to eq DataFoodConsortium::Connector::SuppliedProduct
+    expect(result).to be_a DataFoodConsortium::Connector::SuppliedProduct
     expect(result.semanticType).to eq "https://github.com/datafoodconsortium/ontology/releases/latest/download/DFC_BusinessOntology.owl#SuppliedProduct"
     expect(result.semanticId).to eq "https://example.net/tomato"
     expect(result.name).to eq "Tomato"
@@ -149,7 +149,7 @@ describe DataFoodConsortium::Connector::Importer do
 
     item, tomato = result
 
-    expect(item.class).to eq catalog_item.class
+    expect(item).to be_a catalog_item.class
     expect(item.semanticType).to eq catalog_item.semanticType
     expect(item.semanticId).to eq "https://example.net/tomatoItem"
     expect(tomato.name).to eq "Tomato"
diff --git a/engines/dfc_provider/spec/requests/addresses_spec.rb b/engines/dfc_provider/spec/requests/addresses_spec.rb
index 9848c9244b..21032e5df9 100644
--- a/engines/dfc_provider/spec/requests/addresses_spec.rb
+++ b/engines/dfc_provider/spec/requests/addresses_spec.rb
@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 
-require DfcProvider::Engine.root.join("spec/swagger_helper")
+require_relative "../swagger_helper"
 
 describe "Addresses", type: :request, swagger_doc: "dfc.yaml", rswag_autodoc: true do
   let(:user) { create(:oidc_user) }
diff --git a/engines/dfc_provider/spec/requests/catalog_items_spec.rb b/engines/dfc_provider/spec/requests/catalog_items_spec.rb
index 0d401f9090..c082630044 100644
--- a/engines/dfc_provider/spec/requests/catalog_items_spec.rb
+++ b/engines/dfc_provider/spec/requests/catalog_items_spec.rb
@@ -15,7 +15,7 @@ describe "CatalogItems", type: :request, swagger_doc: "dfc.yaml",
   let(:product) {
     create(
       :base_product,
-      supplier: enterprise, name: "Apple", description: "Red",
+      id: 90_000, supplier: enterprise, name: "Apple", description: "Red",
       variants: [variant],
     )
   }
diff --git a/engines/dfc_provider/spec/requests/enterprises_spec.rb b/engines/dfc_provider/spec/requests/enterprises_spec.rb
index 3c3835452f..0e5f885490 100644
--- a/engines/dfc_provider/spec/requests/enterprises_spec.rb
+++ b/engines/dfc_provider/spec/requests/enterprises_spec.rb
@@ -22,7 +22,7 @@ describe "Enterprises", type: :request, swagger_doc: "dfc.yaml", rswag_autodoc:
   let!(:product) {
     create(
       :base_product,
-      supplier: enterprise, name: "Apple", description: "Round",
+      id: 90_000, supplier: enterprise, name: "Apple", description: "Round",
       variants: [variant],
     )
   }
diff --git a/engines/dfc_provider/spec/requests/supplied_products_spec.rb b/engines/dfc_provider/spec/requests/supplied_products_spec.rb
index b310fff021..a3e2ed2d77 100644
--- a/engines/dfc_provider/spec/requests/supplied_products_spec.rb
+++ b/engines/dfc_provider/spec/requests/supplied_products_spec.rb
@@ -9,6 +9,7 @@ describe "SuppliedProducts", type: :request, swagger_doc: "dfc.yaml",
   let!(:product) {
     create(
       :base_product,
+      id: 90_000,
       supplier: enterprise, name: "Pesto", description: "Basil Pesto",
       variants: [variant],
     )
@@ -78,7 +79,7 @@ describe "SuppliedProducts", type: :request, swagger_doc: "dfc.yaml",
           example.metadata[:operation][:parameters].first[:schema][:example]
         end
 
-        it "creates a variant" do |example|
+        it "creates a product and variant" do |example|
           expect { submit_request(example.metadata) }
             .to change { enterprise.supplied_products.count }.by(1)
 
@@ -87,16 +88,44 @@ describe "SuppliedProducts", type: :request, swagger_doc: "dfc.yaml",
             %r|^http://test\.host/api/dfc/enterprises/10000/supplied_products/[0-9]+$|
           )
 
+          spree_product_id = json_response["ofn:spree_product_id"].to_i
+
           variant_id = dfc_id.split("/").last.to_i
           variant = Spree::Variant.find(variant_id)
           expect(variant.name).to eq "Apple"
           expect(variant.unit_value).to eq 3
+          expect(variant.product_id).to eq spree_product_id
+
+          # References the associated Spree::Product
+          product_id = json_response["ofn:spree_product_id"]
+          product = Spree::Product.find(product_id)
+          expect(product.name).to eq "Apple"
+          expect(product.variants).to eq [variant]
+
+          # Creates a variant for existing product
+          supplied_product[:'ofn:spree_product_id'] = product_id
+          supplied_product[:'dfc-b:hasQuantity'][:'dfc-b:value'] = 6
+
+          expect {
+            submit_request(example.metadata)
+            product.variants.reload
+          }
+            .to change { product.variants.count }.by(1)
+
+          variant_id = json_response["@id"].split("/").last.to_i
+          second_variant = Spree::Variant.find(variant_id)
+          expect(product.variants).to match_array [variant, second_variant]
+          expect(second_variant.unit_value).to eq 6
 
           # Insert static value to keep documentation deterministic:
           response.body.gsub!(
             "supplied_products/#{variant_id}",
             "supplied_products/10001"
           )
+            .gsub!(
+              "\"ofn:spree_product_id\":#{spree_product_id}",
+              '"ofn:spree_product_id":90000'
+            )
         end
       end
     end
@@ -116,6 +145,7 @@ describe "SuppliedProducts", type: :request, swagger_doc: "dfc.yaml",
 
         run_test! do
           expect(response.body).to include variant.name
+          expect(json_response["ofn:spree_product_id"]).to eq 90_000
         end
       end
 
diff --git a/engines/dfc_provider/spec/services/address_builder_spec.rb b/engines/dfc_provider/spec/services/address_builder_spec.rb
index 72fc0f08c0..660c7781ae 100644
--- a/engines/dfc_provider/spec/services/address_builder_spec.rb
+++ b/engines/dfc_provider/spec/services/address_builder_spec.rb
@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 
-require DfcProvider::Engine.root.join("spec/spec_helper")
+require_relative "../spec_helper"
 
 describe AddressBuilder do
   subject(:result) { described_class.address(address) }
diff --git a/swagger/dfc.yaml b/swagger/dfc.yaml
index 8927ccfc1d..f08222b960 100644
--- a/swagger/dfc.yaml
+++ b/swagger/dfc.yaml
@@ -118,6 +118,7 @@ paths:
                       dfc-b:lifetime: ''
                       dfc-b:usageOrStorageCondition: ''
                       dfc-b:totalTheoreticalStock: 0.0
+                      ofn:spree_product_id: 90000
                     - "@id": http://test.host/api/dfc/enterprises/10000/offers/10001
                       "@type": dfc-b:Offer
                       dfc-b:price: 19.99
@@ -341,6 +342,7 @@ paths:
                       dfc-b:lifetime: ''
                       dfc-b:usageOrStorageCondition: ''
                       dfc-b:totalTheoreticalStock: 0.0
+                      ofn:spree_product_id: 90000
                     - "@id": http://test.host/api/dfc/enterprises/10000/catalog_items/10001
                       "@type": dfc-b:CatalogItem
                       dfc-b:references: http://test.host/api/dfc/enterprises/10000/supplied_products/10001
@@ -409,6 +411,7 @@ paths:
                     dfc-b:lifetime: ''
                     dfc-b:usageOrStorageCondition: ''
                     dfc-b:totalTheoreticalStock: 0.0
+                    ofn:spree_product_id: 90000
       requestBody:
         content:
           application/json:
@@ -471,6 +474,7 @@ paths:
                     dfc-b:lifetime: ''
                     dfc-b:usageOrStorageCondition: ''
                     dfc-b:totalTheoreticalStock: 0.0
+                    ofn:spree_product_id: 90000
         '404':
           description: not found
     put: