• Speculation and concern from a naive observer:

    Is it polymarket presenting this ability to detect insiders? Or is someone trying to sell the service of detecting insiders to those wanting to know if bets are on equal footing? (or wanting to follow insiders? or wanting to hide your identity by making multiple accounts? Are there per-account fees, when polymarket might encourage people to make multiple accounts?)

    Regardless, polymarket seems to be on balance corrupting, by monetizing and normalizing use of inside information, which violates agency principles. It's not clear that it really offers hedging or predictive benefits.

    When trading firms do better (after data discovery and analysis), there's some evidence they're better than other firms, and you can trust them with some money. But when there's a public prediction market, the only benefit is to the insiders.

    • Post author here: To clarify, this is not a post from Polymarket.

      This is talking about using Compound AI (product I'm working on) to query Polymarket data, including finding insiders, just as a fun example analysis you could do.

      Often you need a well-calibrated probability of a future event to feed into some other analysis, and Polymarket is pretty great for that. An example is how much insurance (hedge) to buy for some disastrous event.

      • Why dont you just copy the trades?
        • If I'm an insider with 100% confidence, I'll take all offers at a certain price as long as I can afford it. Similar story for lower levels of confidence (but still inside info). There won't necessarily be any left for you to copy at a viable price.
        • Past performance is not an indicator of future performance.
          • Shouldn't it be if you suspect they are executed by an insider?
            • You can't be sure that they are an insider or lucky, just from onchain data.
    • This is largely the classical objection to prediction markets. But prediction markets do have value to outside of the markets because people want to know the future.
  • >Prediction markets have been called "truth machines" because anyone who has information missing from the market can profit.

    That sounds like "insider trading" machines, or "scam" machines, rather than truth machines.

    • yes, they allow you to pay people who have information about the future for that information, in a distributed manner. this is great if, like many people, you want information about the future.
      • Information about the future without power to do anything about it (except bet on it), like is the case for most information and most people, is useless.
      • That sounds cool and fancy in theory, but how do you find that information among the noise?

        like if 50 ppl vote A, 45 people vote B and 1 person who actually knows their shit votes B?

        How do you find it? By amount?

        • Because the people who are consistently right will consistently win money and will make bigger bets which move the price more, in the limit case making the price converge on the true probability of the outcome.

          This is the theoretical underpinning of prediction markets.

        • Apart from minor effects, the price is the probability. If you 'know your shit', you have more confidence and thus bid up or down until there are no more counterparties willing to accept your price, and thus the price settles at approximately the expert/insider probability.
  • Isn’t this the motivation behind polymarket? To incentivize those that have information to bet as a signal of “truth”. What I don’t get is why would anyone bet on this stuff that don’t have insider information besides those with gambling addiction.
    • It is for people like me. I'm usually right about things before other people even know about them. Bought BTC in 2011, ETH in 2014 (funded the IPO), Tesla in 2013, Microsoft right when they replaced Ballmer (at $30 I think), Nvidia on the Covid crash day in 2020, learned Rust in 2017, took AI seriously two weeks after ChatGPT 3.5 launched. I never had any insider information. I typically have a good feeling for things.
    • It's not just a gambling addiction, but many people consider themselves smarter than the average person, and nature's way of punishing these people is creating things like stock markets and polymarkets.
    • It’s a gambling site. The motivation behind it is to make money through transaction fees. You can bet on sports games too.
    • There’s also a vague argument around hedging some actual risks that some market participants genuinely want to hedge… which depends a lot on the specific bet. Eg hedging exposure to specific political events, wars or even company announcements can be relevant and worth a premium for non-insiders. Where there’s a premium to be collected there are speculators to do so.
    • Some people have better data, like insiders.

      Some have better models that predict with higher accuracy, given the same data.

    • Because taking high variance slightly negative EV shots is not a terrible strategy when you have a long time horizon.
      • this is the "lose money on every sale but make it up on scale" version for gamblers and I love that for you.
      • By “not terrible” you mean “bad but not very bad” and not “good” right?
        • "High variance, slightly-negative EV shots on a long time horizon" is a gambling addict's way of justifying the old adage, "sure, we're losing money on each sale, but we'll make up for it in volume!"
  • > Clearly, these insiders have figured out a way to cash in on information. Whether that's kosher is out-of-scope here

    To the extent that the value of prediction markets is in their power to predict, insider trading is kosher. Wholesome even.

    • Bribing employees to disclose confidential information entrusted to them is not kosher nor wholesome. I consider corporate insider trading on these markets to be analogous - if you're an employee and you trade, you are selling your employer's info for money. Nearly every employer would fire employees caught giving away confidential information for personal bribes.

      In the stock market, Matt Levine likes to say that insider training is about theft, not fairness. You can be prosecuted for merely sharing info with a friend on a golf course who then proceeds to trade. Your crime is not trading (you didn't even trade), but misappropriating information you were entrusted with and not authorized to sell.

      • The market economy is not about fairness but about ruthless power.

        The worlds most influential people demonstrate that only power matters; that the world order we built last century through unimaginable suffering and violence matters less than securing their own personal gain; that law, morals, and order were just dreams of the weak

    • It's not that it's cheating _in the market_, but if people have an obligation to their employers, etc, to keep information confidential, then they are stealing from their employer by cashing in on it, as sure as if they had taken money from the till.
    • What about bets without insider participation, where you want the market to function as an aggregator of educated guesses? OP has one reaction to insider trading, but I imagine a very common alternative would be "those insiders make their money off of bettors like me, I shouldn't participate." Some questions are clearly insider-proof, but I imagine many questions have insiders who don't bet on Polymarket. If Polymarket is going to be a good prediction market, surely it should incentivize people to make predictions on those questions too?
    • Indeed. For those of us not gambling, it's really quite beneficial.
      • Prediction markets can only pay out based on public information, which means that prediction markets can only "reveal information" like this for things that would have been public knowledge anyway. And insiders are always risking that leaking their insider info might influence the outcome of the bet against them (like if leaking the date of a covert military operation causes the operation to be rescheduled), so they're financially incentivized to wait as long as possible before tacitly revealing that information. So prediction markets are the worst possible way of revealing hidden information: you will only learn about things you would have already known, and only when it's too late to make any use of that knowledge.
        • You're overlooking that sudden, unexplained or counterintuitive movements in the actual prediction market itself, well before the event occurs/market resolves can themselves convey information, about what apparent insiders think (or whales want to manipulate the market to think).

          Obvious example: Polymarket now has 69(!) markets involving Iran: https://polymarket.com/predictions/iran

          Consider the timing of those markets wrt 2026 national elections in US, Israel, also Sweden, legislative elections in France, Germany (as canaries for their next general elections) plus a possible change in UK PM, plus any possible Ukraine or Venezuela outcomes. And of course events in the stock market or energy markets make certain outcomes more/less likely.

          Also, on Polymarket traders often buy and sell before a market resolves, to exploit patterns in other traders.

          And consider what happens at major media e.g. CNN now they've partnered with Kalshi, wrt whether the broadcasting certain predictions/viewpoints/interviewees get boosted/suppressed.

          • > movements in the actual prediction market itself, well before the event occurs/market resolves can themselves convey information, about what apparent insiders think (or whales want to manipulate the market to think)

            Yes, and surely you see that the inability to distinguish between true signal and deliberate countersignal until after the bet has resolved is an indictment of the very model of predictions markets. Like a qubit, you must collapse the waveform to extract the information.

        • There's also a financial incentive to get your bets in early, while the odds are still in your favor. The longer you wait, the higher the risk that your secret becomes public knowledge.

          I agree it's not perfect, but I think you're underplaying a lot of the value.

  • there is some inevitable "insider trading" in commodities markets. for example if you're a giant agricultural company, and you want to hedge the price of soybeans, you have some extremely relevant insider information about the soybean market. but you're still allowed to trade soybean futures. very different than securities.

    if prediction market contracts really are regulated as commodities, then presumably a lot of insider trading must be legal, although there must be limits of one kind or another and probably if you do something really egregious you might be prosecuted under some legal theory.

    • An agricultural company hedging the price of soybeans is precisely hedging, not speculation. The insider information they have is their supply/demand/pricing picture. That's different than the colloquial definition of insider information which I've always taken to tie to event occurrence (or not).
      • Why not both? They also have insider information and aren't required to limit their trades to those which would hedge the crops.
  • Not sure why the dumb money keeps playing. If you're not the insider the person you're trading against is.
    • Because its an event contract with a defined upside/downside and time horizon. You know exactly what you stand to lose and gain and when. Makes it a valuable part of some intricate financial strategies.
    • "the dumb money"
    • Because you think you can predict the probability of the insider insidering each way and place a bet before they insider
  • > “Hedge funds invest a ton in "alternative data", like credit card transaction data or satellite-imagery (are Walmart's parking lots full?) and need to process as much relevant information as possible to make predictions that are relevant to investments. “

    Ah yes the famous credit card data and Walmart parking lots example that hedge funds were giving a few years ago in every interview and news article. Safe to assume that specifically these data sets are not what you should look at to make money.

  • iirc polymarket doesn't explicitly rule against this, and neither does the law. prediction trading like this operates as "commodities" trading, so they have no obligation to prevent this, and indeed they have an financial incentive to let it continue (assuming others don't leave the platform!)
    • I would go even further and say that it's a vital part of prediction markets as the intended theoretical goal is accuracy of predictions.
  • Out of curiosity, is it possible to see everyone's bets and positions in real time?

    Or is the info only available later?

    I'm guessing that bots predicting insiders and copying positions is already a thing.

    • You can see when they buy or sell a position. It's on the blockchain so it's all public. And yes, copying positions is called copy-trading and it's extremely popular.

      Orders aren't public though. Only the actual trades. This is important because by the time the trade is known by others very often the edge is gone. Especially if you have other people watching the same trader and they all try to copy the trade at the same time.

      • If it takes so long for the actual trades to show up then why is copy-trading popular?
        • Not all strategies are low-latency, so you can copy trade someone with a buy and hold approach. For example someone you think is an insider or whale who might influence the outcome.
  • It baffles me that Polymarket is legal.

    Even if there wasn't any kind of insider betting going on, it just seems so disgusting to turn literally everything into a casino.

    There's a bet going on right now about Jesus coming back before 2027 [1], and a part of me wants to do it because I'm pretty confident Jesus isn't coming back by the end of the year (or any year), but it seems kind of wrong to try and extract money out of people who are gambling away their money.

    [1] https://polymarket.com/event/will-jesus-christ-return-before...

    • The returns on [1] seem to be worse than CDs, and with no government insurance, so it's not worth it at the current payout. But if a religious event spikes the odds, it'll be worth taking the other side of this bet.
      • Yeah, maybe I could fabricate a Nostradamus quote that implies that removing tariffs will spark an apocalypse or something.
    • 0x3f
      Polymarket's legality has not yet been tested in many places, although I don't personally object to it being legal, there's a chance it might not be.

      Also, I'd advise against betting on the Jesus market. You can't actually read the price as a probability here due to time value of money, opportunity cost, etc. So you'd lose money (or at best, gain nothing) by betting against it. It's priced correctly.

      • > Also, I'd advise against betting on the Jesus market. You can't actually read the price as a probability here due to time value of money, opportunity cost, etc. So you'd lose money (or at best, gain nothing) by betting against it. It's priced correctly.

        Yeah, and assuming Jesus doesn't come back that's only about a 3.6% return rate, which is what Treasury Bills are getting right now [1]. At that point I might as well do that and avoid paying state tax on my interest.

        [1] https://home.treasury.gov/resource-center/data-chart-center/...

        • Exactly, the existence of alternatives is mostly what keeps the price non-zero. I think counterparties who are actually betting on Jesus returning will be quite rare. So I wouldn't feel bad about taking money from saps, more about just getting a bad rate of return for yourself.
          • Yeah, maybe a bad example on my end.

            Still, I just find the idea of turning everything in politics into a casino kind of gross. Taken to the extreme it can get pretty disgusting.

            Like, imagine that there were a Polymarket of "Will COVID deaths break 1 million?" or "Will <Insert Serial Killer> Take His Fifth Victim?".

            These are hyperbolic examples and I'm not saying that anything on Polymarket is that bad, but even the stuff that's currently on there right now like "Khamenei out as Supreme Leader of Iran by March 31?" [1] or "Israel strikes Iran by February 28, 2026?" [2] seems kind of crass. These are real issues that have real consequences that affect many real humans (who are no less valuable than me) and people are treating this shit like a fucking game.

            I'm not accusing you of that, to be clear, it's just why I find Polymarket to be gross and I'm not sure it should be legal.

            [1] https://polymarket.com/event/khamenei-out-as-supreme-leader-...

            [2] https://polymarket.com/event/israel-strikes-iran-by-february...

            • The market already bets on war and death, and has done for probably centuries, only it's mostly institutional players. Seems to me Polymarket just democratizes that, both for bettors and potentially consumers of the probabilities.

              I would say the average person is terrible at aggregating media and making predictions, at least this way they can access expert opinion for free.

              Of course as yet it's still niche nerd stuff but if I were in Iran, I'd probably find a signal about imminent strikes or future regime change quite useful.

  • There is 100% insider-trading and manipulation of prediction markets. It's absurd some of the markets that are created. The most glaring example was this years super bowl halftime show. They had markets on songs Bad Bunny would sing, which song he would sing first, etc. You're telling me the thousands of people who had access to practices and information would not wager on this?
    • You can just stand near the stadium during practice and glean this info. I believe people did exactly that.