A special appearance is one made for a limited purpose. It can be made, for example, to challenge the sufficiency of the service of process. But most often, a special appearance is made to challenge the court's personal jurisdiction over the defendant. It prevents a default judgment from being rendered against the defendant for failing to file a PLEADING. (A default judgment is an automatic loss for failing to answer the complaint properly.)
When a defendant makes a special appearance, no other issues may be raised without that appearance's becoming a general appearance. If a party takes any action dealing with the merits of the case, the party is deemed to have made a general appearance and submitted to the jurisdiction of the court.
If a challenge is successful and the court agrees that it does not have personal jurisdiction over the defendant, it will dismiss the action. If the court finds against the defendant on that issue, that decision can later be appealed.
The right to make a special appearance is almost universally recognized, except where abolished by statute. As a rule, leave of court (permission) must be obtained before a special appearance can be made, but this is not always the case.
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