Trump says he's declassifying files about aliens and UFOs. That's going to make some longtime betters on Polymarket very rich.

Alien prediction markets are heating up as Trump vows to release secret UFO files.

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• President Donald Trump says he is going to declassify files about aliens and UFOs.
• That could mean huge payouts for traders betting on alien disclosure on the prediction platform Polymarket.
• Aliens have long occupied a strange but persistent corner of the betting world.

President Donald Trump says he is directing federal agencies to declassify UFO files.