diff --git a/chrome/content/zotero/xpcom/data/collection.js b/chrome/content/zotero/xpcom/data/collection.js
index ef2835fff2..45d736deb7 100644
--- a/chrome/content/zotero/xpcom/data/collection.js
+++ b/chrome/content/zotero/xpcom/data/collection.js
@@ -1008,8 +1008,3 @@ Zotero.Collection.prototype._refreshChildItems = Zotero.Promise.coroutine(functi
 		return this.loadChildItems(true);
 	}
 });
-
-
-Zotero.Collection.prototype._generateKey = function () {
-	return Zotero.Utilities.generateObjectKey();
-}
diff --git a/chrome/content/zotero/xpcom/data/dataObjectUtilities.js b/chrome/content/zotero/xpcom/data/dataObjectUtilities.js
index 0f1172abf2..7391d465e3 100644
--- a/chrome/content/zotero/xpcom/data/dataObjectUtilities.js
+++ b/chrome/content/zotero/xpcom/data/dataObjectUtilities.js
@@ -27,17 +27,32 @@
 Zotero.DataObjectUtilities = {
 	"checkLibraryID": function (libraryID) {
 		if (libraryID === null) {
-			Zotero.debug("Deprecated: libraryID cannot be NULL\n\n" + Components.stack, 2);
+			Zotero.debug("Deprecated: libraryID cannot be NULL", 2, 1);
 		}
 		else {
 			var intValue = parseInt(libraryID);
-			if (libraryID != intValue) {
-				throw new Error("libraryID must be an integer");
+			if (libraryID != intValue || intValue < 0) {
+				throw new Error("libraryID must be a positive integer");
 			}
 		}
 		return intValue;
 	},
 	
+	"checkDataID": function(dataID) {
+		var intValue = parseInt(dataID);
+		if (dataID != intValue || dataID < 0)
+			throw new Error("id must be a positive integer");
+		return intValue;
+	},
+	
+	"checkKey": function(key) {
+		if (!key) return null;
+		if (!Zotero.Utilities.isValidObjectKey(key)) {
+			throw new Error("key is not valid");
+		}
+		return key;
+	},
+	
 	"getObjectTypePlural": function getObjectTypePlural(objectType) {
 		return objectType == 'search' ? 'searches' : objectType + 's';
 	},
diff --git a/chrome/content/zotero/xpcom/id.js b/chrome/content/zotero/xpcom/id.js
index 8db03966a1..4387a963ab 100644
--- a/chrome/content/zotero/xpcom/id.js
+++ b/chrome/content/zotero/xpcom/id.js
@@ -83,13 +83,6 @@ Zotero.ID_Tracker = function () {
 		}
 	});
 	
-	
-	this.isValidKey = function (value) {
-		var re = /^[23456789ABCDEFGHIJKLMNPQRSTUVWXYZ]{8}$/
-		return re.test(value);
-	}
-	
-	
 	function getBigInt(max) {
 		if (!max) {
 			max = 9007199254740991;
diff --git a/chrome/content/zotero/xpcom/search.js b/chrome/content/zotero/xpcom/search.js
index 6f706c1aa1..b7b57e2f5a 100644
--- a/chrome/content/zotero/xpcom/search.js
+++ b/chrome/content/zotero/xpcom/search.js
@@ -1642,13 +1642,6 @@ Zotero.Search.prototype._buildQuery = Zotero.Promise.coroutine(function* () {
 	this._sqlParams = sqlParams.length ? sqlParams : false;
 });
 
-
-Zotero.Search.prototype._generateKey = function () {
-	return Zotero.Utilities.generateObjectKey();
-}
-
-
-
 Zotero.Searches = new function(){
 	Zotero.DataObjects.apply(this, ['search', 'searches', 'savedSearch', 'savedSearches']);
 	this.constructor.prototype = new Zotero.DataObjects();
diff --git a/chrome/content/zotero/xpcom/utilities.js b/chrome/content/zotero/xpcom/utilities.js
index 91b223be86..8649d3c285 100644
--- a/chrome/content/zotero/xpcom/utilities.js
+++ b/chrome/content/zotero/xpcom/utilities.js
@@ -1812,16 +1812,26 @@ Zotero.Utilities = {
 		return Zotero.ItemTypes.getImageSrc(attachment.mimeType === "application/pdf"
 							? "attachment-pdf" : "attachment-snapshot");
 	},
-
+	
+	"allowedKeyChars": "23456789ABCDEFGHIJKLMNPQRSTUVWXYZ",
+	
 	/**
 	 * Generates a valid object key for the server API
 	 */
 	"generateObjectKey":function generateObjectKey() {
-		// TODO: add 'L' and 'Y' after 3.0.11 cut-off
-		var baseString = "23456789ABCDEFGHIJKMNPQRSTUVWXZ";
-		return Zotero.Utilities.randomString(8, baseString);
+		return Zotero.Utilities.randomString(8, Zotero.Utilities.allowedKeyChars);
 	},
-
+	
+	/**
+	 * Check if an object key is in a valid format
+	 */
+	"isValidObjectKey":function(key) {
+		if (!Zotero.Utilities.objectKeyRegExp) {
+			Zotero.Utilities.objectKeyRegExp = new RegExp('^[' + Zotero.Utilities.allowedKeyChars + ']{8}$');
+		}
+		return Zotero.Utilities.objectKeyRegExp.test(key);
+	},
+	
 	/**
 	 * Provides unicode support and other additional features for regular expressions
 	 * See https://github.com/slevithan/xregexp for usage