You guessed it. A message circulating on Facebook that founder Mark Zuckerberg is offering up millions of dollars for sharing the post is a hoax.

The rumor is the byproduct of Zuckerberg's recent announcement that he and his wife are giving $45 billion worth of their stock to the Chan Zuckerberg Initiative, to support philanthropic causes in honor of the birth of their daughter, according to NBC News.

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The phony post claims that Zuckerberg is giving away $4.5 million to 1,000 Facebook users who share it after tagging five to 10 friends.

But it's not real.