diff --git a/helper/TypeMapping.js b/helper/TypeMapping.js
index 97d87a26..7f277c3e 100644
--- a/helper/TypeMapping.js
+++ b/helper/TypeMapping.js
@@ -1,6 +1,9 @@
 const _ = require('lodash');
 const elasticsearch = require('elasticsearch');
 
+// a list of the canonical sources included in the default Pelias configuration
+const CANONICAL_SOURCES = ['whosonfirst', 'openstreetmap', 'openaddresses', 'geonames'];
+
 var TypeMapping = function(){
 
   // A list of all sources
@@ -75,6 +78,22 @@ TypeMapping.prototype.generateMappings = function(){
   this.layer_mapping = TypeMapping.addStandardTargetsToAliases(this.layers, this.layer_aliases);
 };
 
+// return a list of all sources which are part of the canonical Pelias configuration
+TypeMapping.prototype.getCanonicalSources = function(){
+  return CANONICAL_SOURCES;
+};
+
+// generate a list of all layers which are part of the canonical Pelias configuration
+TypeMapping.prototype.getCanonicalLayers = function(){
+  var canonicalLayers = [];
+  for( var source in this.layers_by_source ){
+    if( _.includes( CANONICAL_SOURCES, source ) ){
+      canonicalLayers = _.uniq( canonicalLayers.concat( this.layers_by_source[source] ) );
+    }
+  }
+  return canonicalLayers;
+};
+
 // load values from targets block
 TypeMapping.prototype.loadTargets = function( targetsBlock ){
 
diff --git a/helper/diffPlaces.js b/helper/diffPlaces.js
index ea15bd79..0f327bfb 100644
--- a/helper/diffPlaces.js
+++ b/helper/diffPlaces.js
@@ -1,5 +1,6 @@
 const _ = require('lodash');
 const placeTypes = require('./placeTypes');
+const canonicalLayers = require('../helper/type_mapping').getCanonicalLayers();
 const field = require('../helper/fieldValue');
 
 /**
@@ -7,7 +8,15 @@ const field = require('../helper/fieldValue');
  * Returns false if the objects are the same, else true.
  */
 function isLayerDifferent(item1, item2){
-  return isPropertyDifferent(item1, item2, 'layer');
+  if( isPropertyDifferent(item1, item2, 'layer') ){
+    // consider all custom layers to be analogous to a venue
+    if( ( item1.layer === 'venue' || !_.includes( canonicalLayers, item1.layer ) ) &&
+        ( item2.layer === 'venue' || !_.includes( canonicalLayers, item2.layer ) ) ){
+      return false;
+    }
+    return true;
+  }
+  return false;
 }
 
 /**
diff --git a/middleware/dedupe.js b/middleware/dedupe.js
index ba9e70e7..175c5887 100644
--- a/middleware/dedupe.js
+++ b/middleware/dedupe.js
@@ -1,6 +1,7 @@
 const logger = require('pelias-logger').get('api');
 const _ = require('lodash');
 const isDifferent = require('../helper/diffPlaces').isDifferent;
+const canonicalSources = require('../helper/type_mapping').getCanonicalSources();
 const field = require('../helper/fieldValue');
 
 function dedupeResults(req, res, next) {
@@ -74,6 +75,10 @@ function isPreferred(existingHit, candidateHit) {
   if( !_.has(existingHit, 'address_parts.zip') &&
        _.has(candidateHit, 'address_parts.zip') ){ return true; }
 
+  // prefer non-canonical sources over canonical ones
+  if( !_.includes(canonicalSources, candidateHit.source) &&
+       _.includes(canonicalSources, existingHit.source) ){ return true; }
+
   // prefer certain sources over others
   switch( existingHit.source ){
     // sources are the same
diff --git a/test/unit/fixture/dedupe_elasticsearch_custom_layer_results.js b/test/unit/fixture/dedupe_elasticsearch_custom_layer_results.js
new file mode 100644
index 00000000..4c1f5f58
--- /dev/null
+++ b/test/unit/fixture/dedupe_elasticsearch_custom_layer_results.js
@@ -0,0 +1,32 @@
+module.exports = [
+  {
+    '_id': '101914069',
+    'layer': 'venue',
+    'source': 'openstreetmap',
+    'name': {
+      'default': 'Nike World Headquarters'
+    },
+    'parent': {
+      'country_a': ['USA'],
+      'country': ['United States'],
+      'region': ['Oregon'],
+      'region_id': ['85688513']
+    },
+    'confidence': 0.98
+  },
+  {
+    '_id': '2456::trimet::major_employer',
+    'layer': 'major_employer',
+    'source': 'transit',
+    'name': {
+      'default': 'Nike World Headquarters'
+    },
+    'parent': {
+      'country_a': ['USA'],
+      'country': ['United States'],
+      'region': ['Oregon'],
+      'region_id': ['85688513']
+    },
+    'confidence': 0.50
+  }
+];
\ No newline at end of file
diff --git a/test/unit/middleware/dedupe.js b/test/unit/middleware/dedupe.js
index 9b4d04c3..674a2b10 100644
--- a/test/unit/middleware/dedupe.js
+++ b/test/unit/middleware/dedupe.js
@@ -1,5 +1,6 @@
 var data = require('../fixture/dedupe_elasticsearch_results');
 var nonAsciiData = require('../fixture/dedupe_elasticsearch_nonascii_results');
+var customLayerData = require('../fixture/dedupe_elasticsearch_custom_layer_results');
 var dedupe = require('../../../middleware/dedupe')();
 
 module.exports.tests = {};
@@ -56,10 +57,29 @@ module.exports.tests.dedupe = function(test, common) {
       t.end();
     });
   });
+
+  test('deduplicate between custom layers and venue layers', function(t) {
+    var req = {
+      clean: {
+        size: 20
+      }
+    };
+    var res = {
+      data: customLayerData
+    };
+    var expected = customLayerData[1]; // non-canonical record
+
+    dedupe(req, res, function () {
+      t.equal(res.data.length, 1, 'only one result displayed');
+      t.equal(res.data[0], expected, 'non-canonical data is preferred');
+      t.end();
+    });
+  });
 };
 
-module.exports.tests.trump = function(test, common) {
-  test('whosonfirst trumps geonames, replace', function (t) {
+
+module.exports.tests.priority = function(test, common) {
+  test('whosonfirst takes priority over geonames, replace', function (t) {
     var req = {
       clean: {
         text: 'Lancaster',
@@ -91,7 +111,7 @@ module.exports.tests.trump = function(test, common) {
     });
   });
 
-  test('whosonfirst trumps geonames, no replace', function (t) {
+  test('whosonfirst takes priority over geonames, no replace', function (t) {
     var req = {
       clean: {
         text: 'Lancaster',
@@ -123,7 +143,7 @@ module.exports.tests.trump = function(test, common) {
     });
   });
 
-  test('openstreetmap trumps whosonfirst venues', function (t) {
+  test('openstreetmap takes priority over whosonfirst venues', function (t) {
     var req = {
       clean: {
         text: 'Lancaster Dairy Farm',
@@ -155,7 +175,7 @@ module.exports.tests.trump = function(test, common) {
     });
   });
 
-  test('openaddresses trumps openstreetmap', function (t) {
+  test('openaddresses takes priority over openstreetmap', function (t) {
     var req = {
       clean: {
         text: '100 Main St',
@@ -187,7 +207,7 @@ module.exports.tests.trump = function(test, common) {
     });
   });
 
-  test('openaddresses with zip trumps openaddresses without zip', function (t) {
+  test('openaddresses with zip takes priority over openaddresses without zip', function (t) {
     var req = {
       clean: {
         text: '100 Main St',
@@ -223,7 +243,7 @@ module.exports.tests.trump = function(test, common) {
     });
   });
 
-  test('osm with zip trumps openaddresses without zip', function (t) {
+  test('osm with zip takes priority over openaddresses without zip', function (t) {
     var req = {
       clean: {
         text: '100 Main St',