Index: src/wp-admin/includes/template-functions.php
===================================================================
--- src/wp-admin/includes/template-functions.php	(revision 34948)
+++ src/wp-admin/includes/template-functions.php	(working copy)
@@ -847,9 +847,10 @@
 }
 
 /**
- * Add a meta box to an edit form.
+ * Adds a meta box to one or more edit forms.
  *
  * @since 2.5.0
+ * @since 4.4.0 The `$screen` parameter now also accepts an array of screen IDs.
  *
  * @global array $wp_meta_boxes
  *
@@ -857,8 +858,10 @@
  * @param string           $title         Title of the meta box.
  * @param callable         $callback      Function that fills the box with the desired content.
  *                                        The function should echo its output.
- * @param string|WP_Screen $screen        Optional. The screen on which to show the box (like a post
- *                                        type, 'link', or 'comment'). Default is the current screen.
+ * @param string|array|WP_Screen $screen  Optional. The screen or screens on which to show the box
+ *                                        (such as a post type, 'link', or 'comment'). Accepts a single
+ *                                        screen ID, WP_Screen object, or array of screen IDs. Default
+ *                                        is the current screen.
  * @param string           $context       Optional. The context within the screen where the boxes
  *                                        should display. Available contexts vary from screen to
  *                                        screen. Post edit screen contexts include 'normal', 'side',
@@ -874,11 +877,20 @@
 function add_meta_box( $id, $title, $callback, $screen = null, $context = 'advanced', $priority = 'default', $callback_args = null ) {
 	global $wp_meta_boxes;
 
-	if ( empty( $screen ) )
+	if ( empty( $screen ) ) {
 		$screen = get_current_screen();
-	elseif ( is_string( $screen ) )
+	} elseif ( is_string( $screen ) ) {
 		$screen = convert_to_screen( $screen );
+	} elseif ( is_array( $screen ) ) {
+		foreach ( $screen as $single_screen ) {
+			add_meta_box( $id, $title, $callback, $single_screen, $context, $priority, $callback_args );
+		}
+	}
 
+	if ( ! isset( $screen->id ) ) {
+		return;
+	}
+
 	$page = $screen->id;
 
 	if ( !isset($wp_meta_boxes) )
@@ -1011,24 +1023,36 @@
 }
 
 /**
- * Remove a meta box from an edit form.
+ * Removes a meta box from one or more edit forms.
  *
  * @since 2.6.0
+ * @since 4.4.0 The `$screen` parameter now also accepts an array of screen IDs.
  *
  * @global array $wp_meta_boxes
  *
  * @param string        $id      String for use in the 'id' attribute of tags.
- * @param string|object $screen  The screen on which to show the box (post, page, link).
+ * @param string|array|WP_Screen $screen The screen or screens on which the meta box is shown (such as a
+ *                                       post type, 'link', or 'comment'). Accepts a single screen ID,
+ *                                       WP_Screen object, or array of screen IDs.
  * @param string        $context The context within the page where the boxes should show ('normal', 'advanced').
  */
-function remove_meta_box($id, $screen, $context) {
+function remove_meta_box( $id, $screen, $context ) {
 	global $wp_meta_boxes;
 
-	if ( empty( $screen ) )
+	if ( empty( $screen ) ) {
 		$screen = get_current_screen();
-	elseif ( is_string( $screen ) )
+	} elseif ( is_string( $screen ) ) {
 		$screen = convert_to_screen( $screen );
+	} elseif ( is_array( $screen ) ) {
+		foreach ( $screen as $single_screen ) {
+			remove_meta_box( $id, $single_screen, $context );
+		}
+	}
 
+	if ( ! isset( $screen->id ) ) {
+		return;
+	}
+
 	$page = $screen->id;
 
 	if ( !isset($wp_meta_boxes) )
Index: tests/phpunit/tests/admin/includesTemplate.php
===================================================================
--- tests/phpunit/tests/admin/includesTemplate.php	(revision 34948)
+++ tests/phpunit/tests/admin/includesTemplate.php	(working copy)
@@ -45,4 +45,67 @@
 		$this->assertEquals('', selected(0,false,false));
 		$this->assertEquals('', checked(0,false,false));
 	}
-}
+
+	public function test_add_meta_box() {
+		global $wp_meta_boxes;
+
+		add_meta_box( 'testbox1', 'Test Metabox', '__return_false', 'post' );
+		
+		$this->assertArrayHasKey( 'testbox1', $wp_meta_boxes['post']['advanced']['default'] );
+	}
+
+	public function test_remove_meta_box() {
+		global $wp_meta_boxes;
+
+		// Add a meta boxes to remove.
+		add_meta_box( 'testbox1', 'Test Metabox', '__return_false', $current_screen = 'post' );
+
+		// Confirm it's there.
+		$this->assertArrayHasKey( 'testbox1', $wp_meta_boxes[ $current_screen ]['advanced']['default'] );
+
+		// Remove the meta box.
+		remove_meta_box( 'testbox1', $current_screen, 'advanced' );
+
+		// Check that it was removed properly (The meta box should be set to false once that it has been removed)
+		$this->assertFalse( $wp_meta_boxes[ $current_screen ]['advanced']['default']['testbox1'] );
+	}
+
+	/**
+	 * @ticket 15000
+	 */
+	public function test_add_meta_box_on_multiple_screens() {
+		global $wp_meta_boxes;
+
+		// Add a meta box to three different post types
+		add_meta_box( 'testbox1', 'Test Metabox', '__return_false', array( 'post', 'comment', 'attachment' ) );
+
+		$this->assertArrayHasKey( 'testbox1', $wp_meta_boxes['post']['advanced']['default'] ); 
+		$this->assertArrayHasKey( 'testbox1', $wp_meta_boxes['comment']['advanced']['default'] );
+		$this->assertArrayHasKey( 'testbox1', $wp_meta_boxes['attachment']['advanced']['default'] );
+	}
+
+	/**
+	 * @ticket 15000
+	 */
+	public function test_remove_meta_box_from_multiple_screens() {
+		global $wp_meta_boxes;
+
+		// Add a meta box to three different screens.
+		add_meta_box( 'testbox1', 'Test Metabox', '__return_false', array( 'post', 'comment', 'attachment' ) );
+
+		// Remove meta box from posts.
+		remove_meta_box( 'testbox1', 'post', 'advanced' );
+
+		// Check that we have removed the meta boxes only from posts
+		$this->assertFalse( $wp_meta_boxes['post']['advanced']['default']['testbox1'] );
+		$this->assertArrayHasKey( 'testbox1', $wp_meta_boxes['comment']['advanced']['default'] );
+		$this->assertArrayHasKey( 'testbox1', $wp_meta_boxes['attachment']['advanced']['default'] );
+
+		// Remove the meta box from the other screens.
+		remove_meta_box( 'testbox1', array( 'comment', 'attachment' ), 'advanced' );
+
+		$this->assertFalse( $wp_meta_boxes['comment']['advanced']['default']['testbox1'] );
+		$this->assertFalse( $wp_meta_boxes['attachment']['advanced']['default']['testbox1'] );
+	}
+
+}
\ No newline at end of file