Winning the bet but losing $500k USD—Polymarket completely blew it this time.

The World Cup is in full swing—have you also placed a few bets in the prediction market?

Can Spain win the championship? Will Mbappé score again? Can Messi, in his last World Cup, finally be crowned as a legend?

You put in dozens or hundreds of dollars, stare at the odds, and your heart races. That sense of participation is so irresistible that countless people can’t stop.

But if one day you get the correct answer, and the platform tells you, “Sorry, the rules changed—you lost.”

How do you feel?

This isn’t hypothetical.

This is what has actually happened on Polymarket over the past two weeks.

Here’s what happened:

On Polymarket there is a prediction market: Will Strategy sell Bitcoin before May 31?

This is a super contract worth more than $140 million, drawing tens of thousands of traders to take part.

After the May 31 deadline—on June 1—Strategy filed documents with the SEC, clearly showing that during the period from May 26 to May 31, the company did, in fact, sell 32 Bitcoins, totaling about $2.5 million.

The “Yes” camp was boiling—facts speak louder than words, the answer was obvious!

However, Polymarket’s handling left everyone stunned.

The platform issued a supplementary statement saying that this sale doesn’t count, because the public disclosure occurred on June 1, beyond the deadline.

Is it “whether they sold before May 31,” or “whether they publicly announced that they sold before May 31”?

Did they add this explanation only after the fact? For a $140 million market—can it be flipped just like that?

The result: the Yes camp was wiped out.

A trader named willo2 went all-in on Yes, putting in $527k and expecting to earn about a 20% arbitrage return. Minutes later, wiped out to zero.

His X post said only one line: “I was just scammed.”

And there was also Hunter Guo, a 20-year-old student at King’s College London. He bought thousands of Yes contracts, expecting to profit about $35k—he even had a Porsche picked out. Minutes later, the contract value dropped to nearly zero.

“I cried for two whole days. That was a lot of money.”

This isn’t a one-off case. According to Polymarket data, in this ruling, 1,838 accounts with a total of $3.8 million in bets were zeroed out.

What’s even more infuriating than losing money: Polymarket hasn’t done this for the first time.

An earlier investigation found that more than 60% of active UMA voters on the platform could be linked to Polymarket accounts, and in about one-fifth of disputed markets, at least one voting party had a conflict of interest. Nine anonymous crypto whale wallets actually hold the power over billions of dollars in disputed contracts.

Wen Wei Po put it more bluntly: Platforms like Polymarket, which wave the banner of “collective intelligence,” are actually evolving into a breeding ground for insider trading and tools to harvest wealth.

To put it plainly: a group of opaque “judges” who hold the power of final interpretation. You think it’s decentralized—when in reality, you’re being centrally carved up.

And what’s the most ironic part?

While this credibility crisis erupts, the prediction market is hitting the biggest traffic peak in history.

With the 2026 World Cup just underway, Polymarket’s World Cup champion market has already surpassed $1.9 billion in total trading volume. Bernstein expects that during the World Cup, betting from the US alone could reach as high as $10 billion.

In March, the number of monthly users in prediction markets rose 118% year over year to 8.65 million. In May, monthly trading volume reached $29.4 billion. In the first week of June, another $6 billion was added—just 12 months ago, monthly volume was only $1.2 billion.

And just yesterday (June 13), Polymarket joined with Kalshi and Crypto com to form the “Fair Markets Alliance,” suing Kentucky’s 14.25% prediction market trading tax, claiming the tax is discriminatory.

On one side is the “Unfair Markets Alliance” that makes users lose $500k. On the other side, they wave the banner of the “Fair Markets Alliance” to sue others for discrimination.

Surreal? It’s surreal.

This isn’t a credibility crisis—it’s a credibility collapse.

So during the World Cup, will you keep playing in the prediction market?

I’m not telling you not to play—World Cup predictions are genuinely exciting. Watching odds move, following teams, feeling your heartbeat—that’s something you can’t get elsewhere.

But remember these three things:

Rules can be changed whenever they want—don’t assume that if you bet right, you’re safe. The trader who lost $527k USD is your warning.

“Collective intelligence” in the face of information asymmetry is a joke. People with insider knowledge will always be faster than you.

Most importantly—credibility can collapse in an instant, but repairing it takes a long time. Once users don’t trust you anymore, no matter how much traffic you have, it’s just a fleeting moment.

“When you think you’re using wisdom to predict the future, don’t forget—someone holds cards you can’t see, and others secretly swap cards after the game.”

During the World Cup, will you keep placing bets in prediction markets? Or have you run into similar unfairness on Polymarket? #我的Gate交易时刻 #TradFiCFD黄金大师赛 #预测世界杯德国VS库拉索 $BTC $ETH