public function isPublished()
    {
        $id = $this->owner->ID ?: $this->owner->OldID;
        if (!$id) {
            return false;
        }

        // Non-staged objects are considered "published" if saved
        if (!$this->hasStages()) {
            return true;
        }

        $liveVersion = static::get_versionnumber_by_stage($this->owner, Versioned::LIVE, $id);
        return (bool)$liveVersion;
    }