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filter is not described

site_option_(option) filter-hook . WP 3.0.0

Filters the value of an existing network option.

The dynamic portion of the hook name, $option, refers to the option name.


add_filter( 'site_option_(option)', 'filter_function_name_5601', 10, 3 );
function filter_function_name_5601( $value, $option, $network_id ){
	// filter...

	return $value;
Value of network option.
Option name.
ID of the network.


  • Since 2.9.0 As 'site_option_' . $key
  • Since 4.4.0 The $option parameter was added.
  • Since 4.7.0 The $network_id parameter was added.

Where the hook is called

wp-includes/option.php 1284
return apply_filters( "site_option_{$option}", $value, $option, $network_id );

Where the hook is used (in WP core)

wp-includes/ms-default-filters.php 21
add_filter( 'site_option_welcome_user_email', 'welcome_user_msg_filter' );
wp-includes/ms-functions.php 2227
remove_filter( 'site_option_welcome_user_email', 'welcome_user_msg_filter' );