WordPress at a glance
filter is not described

the_modified_date filter-hook . WP 2.1.0

Filters the date a post was last modified for display.

Usage

add_filter( 'the_modified_date', 'filter_function_name_7645', 10, 4 );
function filter_function_name_7645( $the_modified_date, $d, $before, $after ){
	// filter...

	return $the_modified_date;
}
$the_modified_date(string)
The last modified date.
$d(string)
PHP date format. option if not specified.
Default: 'date_format'
$before(string)
HTML output before the date.
$after(string)
HTML output after the date.

Where the hook is called

the_modified_date()
the_modified_date
wp-includes/general-template.php 2304
$the_modified_date = apply_filters( 'the_modified_date', $the_modified_date, $d, $before, $after );

Where the hook is used (in WP core)

Does not used.