Opting out means you formally choose to remove yourself from a group lawsuit (a class action) so that you are not bound by any settlement or judgment.
In a class action, the court typically approves a notice to all potential class members explaining that they can exclude themselves by submitting a written request to opt out. If you opt out, you are not part of the lawsuit, meaning you cannot share in any settlement or award, but you also preserve your right to file your own individual lawsuit later.
If you do nothing and remain in the class, you are automatically bound by the outcome—whether favorable or unfavorable. Opting out gives you control over your own claim, but it also means you must pursue it on your own without the leverage of the class.
Many people mistakenly believe opting out is how you join a lawsuit or that it guarantees you compensation. In reality, opting out does the opposite: it excludes you from the case entirely, so you receive nothing from the class settlement.
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This page explains the concept. When it matters to your case, read the rule that governs it in your court — we hold Texas, federal and Washington court rules word for word, and every state's official resources are on the state pages. If someone cites a case at you, check that it exists first.
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General explanation, not legal advice, and not specific to any state — procedures and deadlines vary by jurisdiction and court. If you can get a lawyer or free legal aid, do: every real option.