diff --git a/src/Cookie.php b/src/Cookie.php
index e9ad899b5..b4a38e617 100644
--- a/src/Cookie.php
+++ b/src/Cookie.php
@@ -491,13 +491,19 @@ public static function parse($cookie_header, $name = '', $reference_time = null)
 	 * @param \WpOrg\Requests\Iri|null         $origin  URI for comparing cookie origins
 	 * @param int|null                         $time    Reference time for expiration calculation
 	 * @return array
+	 *
+	 * @throws \WpOrg\Requests\Exception\InvalidArgument When the passed $origin argument is not null or an instance of the Iri class.
 	 */
-	public static function parse_from_headers(Headers $headers, Iri $origin = null, $time = null) {
+	public static function parse_from_headers(Headers $headers, $origin = null, $time = null) {
 		$cookie_headers = $headers->getValues('Set-Cookie');
 		if (empty($cookie_headers)) {
 			return [];
 		}
 
+		if ($origin !== null && !($origin instanceof Iri)) {
+			throw InvalidArgument::create(2, '$origin', Iri::class . ' or null', gettype($origin));
+		}
+
 		$cookies = [];
 		foreach ($cookie_headers as $header) {
 			$parsed = self::parse($header, '', $time);
diff --git a/tests/Cookie/ParseTest.php b/tests/Cookie/ParseTest.php
index 3e29dd713..068ba502b 100644
--- a/tests/Cookie/ParseTest.php
+++ b/tests/Cookie/ParseTest.php
@@ -76,6 +76,37 @@ public function testParseInvalidReferenceTime() {
 		Cookie::parse('test', 'test', 'now');
 	}
 
+	/**
+	 * Verify parsing of cookies fails with an exception if the $origin parameter is passed anything but `null`
+	 * or an instance of Iri.
+	 *
+	 * @dataProvider dataParseFromHeadersInvalidOrigin
+	 *
+	 * @covers ::parse_from_headers
+	 *
+	 * @param mixed $input Invalid parameter input.
+	 *
+	 * @return void
+	 */
+	public function testParseFromHeadersInvalidOrigin($input) {
+		$this->expectException(InvalidArgument::class);
+		$this->expectExceptionMessage('Argument #2 ($origin) must be of type WpOrg\Requests\Iri or null');
+
+		$headers               = new Headers();
+		$headers['Set-Cookie'] = 'name=value';
+
+		Cookie::parse_from_headers($headers, $input);
+	}
+
+	/**
+	 * Data Provider.
+	 *
+	 * @return array
+	 */
+	public static function dataParseFromHeadersInvalidOrigin() {
+		return TypeProviderHelper::getAllExcept(TypeProviderHelper::GROUP_NULL);
+	}
+
 	/**
 	 * Tests receiving an exception when the parse_from_headers() method received an invalid input type as `$reference_time`.
 	 *