diff --git a/src/remote/activitypub/request.ts b/src/remote/activitypub/request.ts
index e4f3018336..bcbb0fbe70 100644
--- a/src/remote/activitypub/request.ts
+++ b/src/remote/activitypub/request.ts
@@ -60,11 +60,6 @@ export default async (user: ILocalUser, url: string, object: any) => {
 			headers: ['date', 'host', 'digest']
 		});
 
-		// Signature: Signature ... => Signature: ...
-		let sig = req.getHeader('Signature')!.toString();
-		sig = sig.replace(/^Signature /, '');
-		req.setHeader('Signature', sig);
-
 		req.on('timeout', () => req.abort());
 
 		req.on('error', e => {
diff --git a/src/server/activitypub.ts b/src/server/activitypub.ts
index 92e23380cb..3094d69b15 100644
--- a/src/server/activitypub.ts
+++ b/src/server/activitypub.ts
@@ -26,8 +26,6 @@ const router = new Router();
 function inbox(ctx: Router.RouterContext) {
 	let signature;
 
-	ctx.req.headers.authorization = `Signature ${ctx.req.headers.signature}`;
-
 	try {
 		signature = httpSignature.parseRequest(ctx.req, { 'headers': [] });
 	} catch (e) {