It's been a few years, but I had a case like this. My client was in your position. The guy who he had the internet-based problem with was in a western state. We sued the our-of-state guy successfully in Florida, and the Florida court had jurisdiction. Without having done the research to answer your question today, I can only say that I would be very surprised if the law has changed. Find a lawyer who knows what to do and sue them in Florida, make them come to you. Good luck!
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The website is immune from suit under the Communications Decency Act, a federal statute, unless you can prove that it has control over the editorial content of what's posted on the website. This is doubtful. Therefore, your cause of action lies against those persons or entities that are posting the defamatory statements. You'll need to show that the court has "personal jurisdiction" over them by the fact that they purposely posted the defamatory statements that reached viewers of the statements here in Florida.
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