diff --git a/src/vs/vscode.d.ts b/src/vs/vscode.d.ts
index c488cd29b57637480bc211a78845e6849b23cebe..8c6a5442b8ea527bd14b46276885bda2571cd2be 100644
--- a/src/vs/vscode.d.ts
+++ b/src/vs/vscode.d.ts
@@ -5495,13 +5495,14 @@ declare module 'vscode' {
 		 * will be matched against the file paths of resulting matches relative to their workspace. Use a [relative pattern](#RelativePattern)
 		 * to restrict the search results to a [workspace folder](#WorkspaceFolder).
 		 * @param exclude  A [glob pattern](#GlobPattern) that defines files and folders to exclude. The glob pattern
-		 * will be matched against the file paths of resulting matches relative to their workspace.
+		 * will be matched against the file paths of resulting matches relative to their workspace. When `undefined` only default excludes will
+		 * apply, when `null` no excludes will apply.
 		 * @param maxResults An upper-bound for the result.
 		 * @param token A token that can be used to signal cancellation to the underlying search engine.
 		 * @return A thenable that resolves to an array of resource identifiers. Will return no results if no
 		 * [workspace folders](#workspace.workspaceFolders) are opened.
 		 */
-		export function findFiles(include: GlobPattern, exclude?: GlobPattern, maxResults?: number, token?: CancellationToken): Thenable<Uri[]>;
+		export function findFiles(include: GlobPattern, exclude?: GlobPattern | null, maxResults?: number, token?: CancellationToken): Thenable<Uri[]>;
 
 		/**
 		 * Save all dirty files.
diff --git a/src/vs/workbench/api/electron-browser/mainThreadWorkspace.ts b/src/vs/workbench/api/electron-browser/mainThreadWorkspace.ts
index b1cd93ae038a84395f04e0d3e5644cf07b76a986..721a2df3e409a12e23853ab6a4acdb9a5128779a 100644
--- a/src/vs/workbench/api/electron-browser/mainThreadWorkspace.ts
+++ b/src/vs/workbench/api/electron-browser/mainThreadWorkspace.ts
@@ -97,7 +97,7 @@ export class MainThreadWorkspace implements MainThreadWorkspaceShape {
 
 	// --- search ---
 
-	$startSearch(includePattern: string, includeFolder: string, excludePattern: string, maxResults: number, requestId: number): Thenable<URI[]> {
+	$startSearch(includePattern: string, includeFolder: string, excludePatternOrDisregardExcludes: string | false, maxResults: number, requestId: number): Thenable<URI[]> {
 		const workspace = this._contextService.getWorkspace();
 		if (!workspace.folders.length) {
 			return undefined;
@@ -129,7 +129,8 @@ export class MainThreadWorkspace implements MainThreadWorkspaceShape {
 			type: QueryType.File,
 			maxResults,
 			includePattern: { [typeof includePattern === 'string' ? includePattern : undefined]: true },
-			excludePattern: { [typeof excludePattern === 'string' ? excludePattern : undefined]: true },
+			excludePattern: { [typeof excludePatternOrDisregardExcludes === 'string' ? excludePatternOrDisregardExcludes : undefined]: true },
+			disregardExcludeSettings: excludePatternOrDisregardExcludes === false,
 			useRipgrep,
 			ignoreSymlinks
 		};
@@ -168,4 +169,4 @@ export class MainThreadWorkspace implements MainThreadWorkspaceShape {
 			return result.results.every(each => each.success === true);
 		});
 	}
-}
\ No newline at end of file
+}
diff --git a/src/vs/workbench/api/node/extHost.protocol.ts b/src/vs/workbench/api/node/extHost.protocol.ts
index e289cf18c822fffc6996e16b9fd75e2be8901ffa..cd5e404db146593dc64b5047aad6214e9a50d84e 100644
--- a/src/vs/workbench/api/node/extHost.protocol.ts
+++ b/src/vs/workbench/api/node/extHost.protocol.ts
@@ -346,7 +346,7 @@ export interface MainThreadTelemetryShape extends IDisposable {
 }
 
 export interface MainThreadWorkspaceShape extends IDisposable {
-	$startSearch(includePattern: string, includeFolder: string, excludePattern: string, maxResults: number, requestId: number): Thenable<UriComponents[]>;
+	$startSearch(includePattern: string, includeFolder: string, excludePatternOrDisregardExcludes: string | false, maxResults: number, requestId: number): Thenable<UriComponents[]>;
 	$cancelSearch(requestId: number): Thenable<boolean>;
 	$saveAll(includeUntitled?: boolean): Thenable<boolean>;
 	$updateWorkspaceFolders(extensionName: string, index: number, deleteCount: number, workspaceFoldersToAdd: { uri: UriComponents, name?: string }[]): Thenable<void>;
diff --git a/src/vs/workbench/api/node/extHostTypeConverters.ts b/src/vs/workbench/api/node/extHostTypeConverters.ts
index 38ce5b918897175d83a76e0b145f0eda497cf549..366a64d45f480dccc24489b56d17f2247cf3cd4c 100644
--- a/src/vs/workbench/api/node/extHostTypeConverters.ts
+++ b/src/vs/workbench/api/node/extHostTypeConverters.ts
@@ -603,11 +603,11 @@ export function toGlobPattern(pattern: vscode.GlobPattern): string | IRelativePa
 		return pattern;
 	}
 
-	if (!isRelativePattern(pattern)) {
-		return undefined;
+	if (isRelativePattern(pattern)) {
+		return new types.RelativePattern(pattern.base, pattern.pattern);
 	}
 
-	return new types.RelativePattern(pattern.base, pattern.pattern);
+	return pattern; // preserve `undefined` and `null`
 }
 
 function isRelativePattern(obj: any): obj is vscode.RelativePattern {
diff --git a/src/vs/workbench/api/node/extHostWorkspace.ts b/src/vs/workbench/api/node/extHostWorkspace.ts
index 5ead32afa25fa33a5b37aa8097163b04465b9dcc..ec70503062e4383796499dc002499392177b42da 100644
--- a/src/vs/workbench/api/node/extHostWorkspace.ts
+++ b/src/vs/workbench/api/node/extHostWorkspace.ts
@@ -331,16 +331,18 @@ export class ExtHostWorkspace implements ExtHostWorkspaceShape {
 			}
 		}
 
-		let excludePattern: string;
-		if (exclude) {
+		let excludePatternOrDisregardExcludes: string | false;
+		if (exclude === null) {
+			excludePatternOrDisregardExcludes = false;
+		} else if (exclude) {
 			if (typeof exclude === 'string') {
-				excludePattern = exclude;
+				excludePatternOrDisregardExcludes = exclude;
 			} else {
-				excludePattern = exclude.pattern;
+				excludePatternOrDisregardExcludes = exclude.pattern;
 			}
 		}
 
-		const result = this._proxy.$startSearch(includePattern, includeFolder, excludePattern, maxResults, requestId);
+		const result = this._proxy.$startSearch(includePattern, includeFolder, excludePatternOrDisregardExcludes, maxResults, requestId);
 		if (token) {
 			token.onCancellationRequested(() => this._proxy.$cancelSearch(requestId));
 		}