Themeforest — Excluding your plugin or theme from update checks

name-collision.php

# For plugins
function cws_hidden_plugin_12345( $r, $url ) {
    if ( 0 !== strpos( $url, 'http://api.wordpress.org/plugins/update-check' ) )
        return $r; // Not a plugin update request. Bail immediately.
  
    $plugins = unserialize( $r['body']['plugins'] );
    unset( $plugins->plugins[ plugin_basename( __FILE__ ) ] );
    unset( $plugins->active[ array_search( plugin_basename( __FILE__ ), $plugins->active ) ] );
    $r['body']['plugins'] = serialize( $plugins );
    return $r;
}
 
add_filter( 'http_request_args', 'cws_hidden_plugin_12345', 5, 2 );



# For themes:
function cws_hidden_theme_12345( $r, $url ) {
    if ( 0 !== strpos( $url, 'http://api.wordpress.org/themes/update-check' ) )
        return $r; // Not a theme update request. Bail immediately.
 
    $themes = unserialize( $r['body']['themes'] );
    unset( $themes[ get_option( 'template' ) ] );
    unset( $themes[ get_option( 'stylesheet' ) ] );
    $r['body']['themes'] = serialize( $themes );
    return $r;
}
 
add_filter( 'http_request_args', 'cws_hidden_theme_12345', 5, 2 );