diff --git a/src/vs/workbench/api/node/extHost.api.impl.ts b/src/vs/workbench/api/node/extHost.api.impl.ts
index f1643edcfaa..739c4bea73c 100644
--- a/src/vs/workbench/api/node/extHost.api.impl.ts
+++ b/src/vs/workbench/api/node/extHost.api.impl.ts
@@ -96,7 +96,7 @@ export function createApiFactory(initData: IInitData, threadService: IThreadServ
 
 		if (extension.enableProposedApi) {
 
-			if (initData.environment.isBuilt && !initData.environment.extensionDevelopmentPath) {
+			if (!initData.environment.enableProposedApi) {
 				extension.enableProposedApi = false;
 				console.warn('PROPOSED API is only available when developing an extension');
 
diff --git a/src/vs/workbench/api/node/extHost.protocol.ts b/src/vs/workbench/api/node/extHost.protocol.ts
index 6637c5b3e35..c22d192f2ee 100644
--- a/src/vs/workbench/api/node/extHost.protocol.ts
+++ b/src/vs/workbench/api/node/extHost.protocol.ts
@@ -39,7 +39,7 @@ import { IApplyEditsOptions, TextEditorRevealType, ITextEditorConfigurationUpdat
 import { InternalTreeExplorerNodeContent } from 'vs/workbench/parts/explorers/common/treeExplorerViewModel';
 
 export interface IEnvironment {
-	isBuilt: boolean;
+	enableProposedApi: boolean;
 	appSettingsHome: string;
 	disableExtensions: boolean;
 	userExtensionsHome: string;
diff --git a/src/vs/workbench/electron-browser/extensionHost.ts b/src/vs/workbench/electron-browser/extensionHost.ts
index a5cf60ef1cc..cfaa68afc02 100644
--- a/src/vs/workbench/electron-browser/extensionHost.ts
+++ b/src/vs/workbench/electron-browser/extensionHost.ts
@@ -21,6 +21,7 @@ import { ITelemetryService } from 'vs/platform/telemetry/common/telemetry';
 import { IWindowIPCService } from 'vs/workbench/services/window/electron-browser/windowService';
 import { ChildProcess, fork } from 'child_process';
 import { ipcRenderer as ipc } from 'electron';
+import product from 'vs/platform/product';
 import { IEnvironmentService } from 'vs/platform/environment/common/environment';
 import { ReloadWindowAction } from 'vs/workbench/electron-browser/actions';
 import { IInstantiationService } from 'vs/platform/instantiation/common/instantiation';
@@ -249,12 +250,13 @@ export class ExtensionHostProcessWorker {
 			let initData: IInitData = {
 				parentPid: process.pid,
 				environment: {
-					isBuilt: this.environmentService.isBuilt,
 					appSettingsHome: this.environmentService.appSettingsHome,
 					disableExtensions: this.environmentService.disableExtensions,
 					userExtensionsHome: this.environmentService.extensionsPath,
 					extensionDevelopmentPath: this.environmentService.extensionDevelopmentPath,
-					extensionTestsPath: this.environmentService.extensionTestsPath
+					extensionTestsPath: this.environmentService.extensionTestsPath,
+					// globally disable proposed api when built and not insiders developing extensions
+					enableProposedApi: !this.environmentService.isBuilt || (!!this.environmentService.extensionDevelopmentPath && product.nameLong.indexOf('Insiders') >= 0)
 				},
 				contextService: {
 					workspace: this.contextService.getWorkspace()