Security incident linked to performance-monitoring tool spurred platform to halt trading for about an hour

Polymarket temporarily halted trading on its international platform on Thursday because of a security incident that compromised a third-party provider, the company said.

Trading was paused for about an hour and resumed on Thursday afternoon. The company has promised to fully reimburse any affected traders.

Revelation comes amid mounting concern over online prediction market’s effects on integrity of financial system

UK authorities are being urged to intervene after it emerged that the online prediction market Polymarket has been taking thousands of dollars worth of bets over whether HSBC and Lloyds will fail.

Polymarket – the US-owned company which holds bets on anything from football matches, to the existence of aliens, to when a bomb drops on a city – has allowed users to take $77,507 (£58,530) worth of positions on whether the world’s biggest banks will go under by the end of this year.

As LeBron James and other NBA stars wholeheartedly embrace the murk of betting and prediction markets, the San Antonio Spurs’ 22-year-old cornerstone has drawn a refreshing line

If the song from LeBron James’s agonizing Polymarket ad is as stuck in your head as mine thanks to the commercial playing during every YouTube video and HBO show (all I wanted to do was rewatch The Leftovers), let Victor Wembanyama be your antidote. At the Spurs’ practice on Thursday, San Antonio Express-News columnist Mike Finger asked Wembanyama if he would ever partner with a sports betting firm. It couldn’t have been easier for the 22-year-old to say yes. The NBA displays ads for both FanDuel and DraftKings, in addition to hawking betting odds on its broadcasts. Until the streaming service met its end a few months ago, plenty of NBA games streamed exclusively on FanDuel Sports Network. Then there are Wembanyama’s legendary peers: James is the new face of Polymarket; Kevin Durant reads FanDuel odds and invests in Kalshi; Giannis Antetokounmpo is a Kalshi shareholder.

“Absolutely not,” Wembanyama said instead. “I will never do that. Honestly, I think it’s very sad to see some players promote it. Everybody does whatever they want, but without me.”

Prediction markets are focusing on extreme weather and the climate crisis. But it’s led to questions about what exactly people are betting on

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How hot will it get in your nearest city tomorrow? How quickly will the planet’s ice melt and its corals die off? How many huge, costly climate disasters will hit this year? If you’re inclined to do so, you can now place online bets on how the weather and the broader, longer-term climate crisis will play out.

In the US, big online prediction markets like Kalshi and Polymarket are considering a new area of growth beyond mere sport and crypto: the climate itself. Kalshi recently reported 500% growth in weather and climate wagers over the past year, taking the market to a $1.1bn, and is now partnering with the Weather Company, which owns the Weather Channel, to boost its credibility in this new arena.

Huge El Niño projected to cause more than 450,000 deaths by February

‘Planetary boundaries’ necessary for flourishing of life have been massively breached, scientists warn

British people understand the climate crisis threat. Today I’m empowering them to tackle it | Andy Burnham

In this week’s newsletter: As the Guardian launches a year-long project, Our Rivers, we take stock of the issues facing waterways around the world

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The nicknames of the world’s biggest rivers give a sense of how we feel about them: “the great river”, “the river that swallows all rivers”, “Mother Ganga” and “Old father Thames”. They feed and water us, and many other animal species. They carry our trade but also give us cool relief on a hot day. They’re nerve endings, elders and sources of comfort, but also of awe and respect.

And yet many of the world’s rivers are suffering, hit by multiple environmental challenges. A new report out today from the World Meteorological Organization finds that rivers across the world experienced one of the driest years in more than three decades during 2025.

Climate crisis probably weakened glacier that caused devastating Nepal-Tibet floods, first study finds

Who are the 514 people accused of starting French wildfires and what motivates them?

Benedict Cumberbatch on his Earth-saving eco film: ‘We are in the last grab of the extraction era’

The actor’s latest promotion has stirred outrage but will no doubt be good for the prediction markets hoping to lure in young men

Prediction markets are a cynical business.

Many customers will lose money, and the real product may just be the delightful dopamine hit that comes in that brief window between placing a bet and its outcome – which is statistically more likely to be a disappointment than a victory. So the bettor has to think they are buying more than their own fleecing.

My parents’ generation may have been on to something when they railed against gambling. If only George Santos had listened

If only George Santos and Bill Simmons had my parents, they wouldn’t be facing down a hailstorm of condemnation for circumventing the basic rules and regulations of dubious “prediction markets” and online gambling. Kalshi just banned the former congressman George Santos from its service and he was forced to pay back his winnings after he was accused of the dumb person’s version of insider trading. He bet on himself to not attend the State of the Union address, then conveniently didn’t go. For his trouble, he won (and will be forced to relinquish) more than $17,000; he’ll also have to pay more than $80,000 in total fines from Kalshi and the Commodity Futures Trading Commission.

Bill Simmons, the sports commentator, podcast host, and founder of The Ringer, had a different story.

The predictions market is planning to allow betting on clinical trial results and regulatory decisions as our family fights for his survival

My son is 12 years old. No matter how many Legos we get him, he will only build robotic mechs. He draws haunting pictures in pen and ink but refuses to take an art class. He was devastated to learn that Chuck E Cheese is phasing out its animatronics. His guidance counselor says he’s so kind, he’s really hard to say no to. He sneezes when he steps out into the sunlight. And he also has a very aggressive tumor growing inches below his heart.

Further, if Kalshi has its way, you could soon be able to bet on health treatments that could be essential to his survival.

Joshua Pederson is professor of humanities at Boston University and the author of Sin Sick: Moral Injury in War and Literature

World Cup and events like Clacton byelection is driving interest in sites such as Polymarket, with UK gamblers easily able to sidestep regulation

With more plot twists than a spy thriller, Argentina’s 3-2 victory over Egypt was one of the World Cup’s most unpredictable matches.

But in one living room in Reading, to the astonishment of his 16-year-old son, a football clairvoyant appeared to know exactly what would happen next.

Prediction sites, which allow bets on all topics from weather to politics, may be in breach of country’s rules

Spain’s ministry of consumer rights has blocked access to Polymarket and Kalshi while it investigates whether the leading prediction market sites are violating Spanish law by operating without a gambling licence.

On Tuesday the ministry said it had launched disciplinary proceedings against the two platforms, which allow users to bet on everything from the weather to political events, amid allegations that they lacked the “necessary administrative authorisation” to operate in Spain.