diff --git a/src/event/validation.ts b/src/event/validation.ts
index 663e034d..8665304a 100644
--- a/src/event/validation.ts
+++ b/src/event/validation.ts
@@ -5,7 +5,7 @@
 
 import { ErrorObject } from "ajv";
 
-export type TypeArray = Int8Array | Uint8Array | Int16Array | Uint16Array | 
+export type TypeArray = Int8Array | Uint8Array | Int16Array | Uint16Array |
   Int32Array | Uint32Array | Uint8ClampedArray | Float32Array | Float64Array;
 
 const globalThisPolyfill = (function() {
@@ -103,7 +103,7 @@ export const base64AsBinary = (base64String: string): Uint8Array => {
   return Uint8Array.from(toBinaryString(base64String), (c) => c.charCodeAt(0));
 };
 
-export const asBase64 = 
+export const asBase64 =
 (value: string | Buffer | TypeArray): string => asBuffer(value).toString("base64");
 
 export const clone = (o: Record<string, unknown>): Record<string, unknown> => JSON.parse(JSON.stringify(o));
diff --git a/src/parsers.ts b/src/parsers.ts
index 7a050672..90b26e52 100644
--- a/src/parsers.ts
+++ b/src/parsers.ts
@@ -89,11 +89,13 @@ export interface MappedParser {
 
 export class DateParser extends Parser {
   parse(payload: string): string {
-    let date = new Date(Date.parse(payload));
-    if (date.toString() === "Invalid Date") {
-      date = new Date();
+    const timestamp = Date.parse(payload);
+    if (isNaN(timestamp)) {
+      // Deprecated: substituting the current time for an unparseable time hides an
+      // invalid message. The spec requires RFC 3339, so v11 will throw a ValidationError.
+      return new Date().toISOString();
     }
-    return date.toISOString();
+    return new Date(timestamp).toISOString();
   }
 }
 
diff --git a/test/conformance/steps.ts b/test/conformance/steps.ts
index 7d53a566..a72203ed 100644
--- a/test/conformance/steps.ts
+++ b/test/conformance/steps.ts
@@ -71,7 +71,11 @@ Then("the attributes are:", function (attributes: { rawTable: [] }) {
   assert.equal(this.cloudevent.id, expected.id);
   assert.equal(this.cloudevent.type, expected.type);
   assert.equal(this.cloudevent.source, expected.source);
-  assert.equal(this.cloudevent.time, new Date(expected.time).toISOString());
+  if (this.cloudevent.time && expected.time) {
+    assert.equal(new Date(this.cloudevent.time).toISOString(), new Date(expected.time).toISOString());
+  } else {
+    assert.equal(this.cloudevent.time, expected.time);
+  }
   assert.equal(this.cloudevent.specversion, expected.specversion);
   assert.equal(this.cloudevent.datacontenttype, expected.datacontenttype);
   return true;
diff --git a/test/integration/parser_test.ts b/test/integration/parser_test.ts
index 5be19b3e..39e72932 100644
--- a/test/integration/parser_test.ts
+++ b/test/integration/parser_test.ts
@@ -6,8 +6,9 @@
 import "mocha";
 import { expect } from "chai";
 
-import { JSONParser as Parser } from "../../src/parsers";
-import { ValidationError } from "../../src/";
+import { DateParser, JSONParser as Parser } from "../../src/parsers";
+import { CloudEvent, ValidationError } from "../../src/";
+import { HTTP } from "../../src/message";
 
 describe("JSON Event Format Parser", () => {
   it("Throw error when payload is an integer", () => {
@@ -79,3 +80,39 @@ describe("JSON Event Format Parser", () => {
     expect(actual).to.be.an("object");
   });
 });
+
+describe("Date Parser", () => {
+  const parser = new DateParser();
+
+  it("Returns an RFC 3339 UTC timestamp unchanged", () => {
+    expect(parser.parse("2018-04-05T17:31:00.000Z")).to.equal("2018-04-05T17:31:00.000Z");
+  });
+
+  it("Normalizes an RFC 3339 timestamp with an offset to UTC", () => {
+    expect(parser.parse("2018-04-05T17:31:00+02:00")).to.equal("2018-04-05T15:31:00.000Z");
+  });
+
+  it("Falls back to the current time when the payload is not a date", () => {
+    const before = Date.now();
+    const parsed = Date.parse(parser.parse("not a date"));
+    const after = Date.now();
+    expect(parsed).to.be.at.least(before).and.at.most(after);
+  });
+
+  it("Does not throw when a binary message carries an unparseable ce-time header", () => {
+    const message = {
+      headers: {
+        "ce-id": "1234",
+        "ce-source": "test",
+        "ce-type": "test.event",
+        "ce-specversion": "1.0",
+        "ce-time": "garbage",
+        "content-type": "application/json",
+      },
+      body: "{}",
+    };
+    const event = HTTP.toEvent(message) as CloudEvent;
+    expect(Number.isNaN(Date.parse(event.time as string))).to.equal(false);
+    expect(() => event.validate()).not.to.throw();
+  });
+});