An Instagram hoax just duped Julia Roberts, Rob Lowe — and the person overseeing our nuclear weapons

A privacy hoax has gone viral — again — tricking celebrities, politicians and probably some of your friends. If you're an Instagram user, you might have seen a very lengthy (and grammatically incorrect) post being shared about the platform's supposed new "rule where they can use your photos."

Here's what you need to know about the revived hoax making the rounds.

What is it?

In the faux-message being shared, users are warned that their photos "can be used in court cases in litigation against you" and, "Everything you've ever posted becomes public from today, Even messages that have been deleted or the photos not allowed." If a person posts the note — which ends stating "Instagram DOES NOT HAVE MY PERMISSION TO SHARE PHOTOS OR MESSAGES" — they apparently are spared.

Many high-profile names quickly spread the message.

The inconsistent font, weird capitalization and grammatical errors didn't deter celebrities from sharing the post. Julia Roberts, Debra Messing, Usher, Rob Lowe, Julianne Moore, Taraji P. Henson and Niall Horan all fell victim.

Secretary of Energy Rick Perry was also duped, much to the delight (and terror) of some people on social media. "Feel free to repost!! #nothanksinstagram," Perry wrote next to the note.

"YOU HANDLE NUCLEAR BOMBS?????" one person commented.

"How the hell are you in charge of the department of energy when you fall for the social media version of chain email," another person exclaimed.

Once he realized he had been tricked, Perry made light of the situation. "I’ll be darned!! First time I’ve seen anything fake on the Internet!!” he commented, before taking the post down Wednesday morning.

A few stars had fun with the whole thing, like John Mayer and Trevor Noah.

So, where did the hoax come from?

Variations of the message have been shared for years. In 2012, a similar one about Facebook claiming copyright to a user's personal information, photographs and other material created similar panic.

"There is a rumor circulating that Facebook is making a change related to ownership of users’ information or the content they post to the site. This is false," the company said in a statement. "Anyone who uses Facebook owns and controls the content and information they post, as stated in our terms. They control how that content and information is shared. That is our policy, and it always has been."

Instagram officially debunked the hoax.

In a statement to Yahoo Entertainment, company spokesperson Stephanie Otway confirmed the viral message is fake: "There’s no truth to this post."

But if you use Instagram, you have already granted the company license to use your content.

A little reminder to anyone with privacy concerns: read the terms of use. While Instagram does not "claim ownership of your content," you have already given the company certain permissions just by signing up.

"When you share, post, or upload content that is covered by intellectual property rights (like photos or videos) on or in connection with our Service, you hereby grant to us a non-exclusive, royalty-free, transferable, sub-licensable, worldwide license to host, use, distribute, modify, run, copy, publicly perform or display, translate, and create derivative works of your content (consistent with your privacy and application settings)," Instagram states on its website. "You can end this license anytime by deleting your content or account. However, content will continue to appear if you shared it with others and they have not deleted it."

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