Normally, every defendant, his attorney, and the attorney for the plaintiff would be obliged to send copies of every filing to each defendant.
In OK, there's a rule specifying that if there's a large number of defendants, copies need not be sent. BUT that's predicated on their being available at the court website, I think.
If you're a participant in the case, I don't think they can say no to such a request. After all, the pleadings in question may have bearing on the entire case. So all defendants, and their attorneys, have the right to see them.