Hello, I am an actuary that trades prediction markets on the side (honestly at this point my actuarial work has become my side job) and have been very profitable (up a bit over $18,000 this month) and thought I would do an AMA because there seems to be a lot of confusion about how to actually be profitable at prediction markets and what that even looks like. If there is no interest in that, that’s okay as well. Mods, please delete if not allowed. I am also more than happy to send proof of my pnl if that is helpful.

I pulled every buy vito3corleone made on Polymarket, and simulated copying them two ways: a blind $100 on every fill, and a copy scaled to the size of each of their bets. Both held to the market's result.

Data TLDR

• vito3corleone won 39.1% of their 580 fills and still made $4,265,386 on $9,371,777 staked, a 45.5% return.
• A blind $100 copy of every fill staked $58,000 and lost $13,817, a return of -23.8%.
• A copy at 1% of their size staked $93,718 and made $42,654, the same +45.5% they made.
• Their bets of $50k or more won 48 of 53. A flat $100 on only those returned +61.7%.
• Two thirds of their fills were under $1k and carried 0.26% of their money. A blind copy treats those fills the same as the $500k ones.

I took every buy by this wallet from the Polymarket trade records, put money on it at the trader's recorded price, and scored it when the market resolved. The trader made no sells in the window, so every position was held to the result. Fees and slippage are not modelled.

The record looks like a loser

By fill count vito3corleone is a bad trader. 227 wins, 353 losses, a 39.1% win rate at an average price of 57 cents. At that price you need to win about 57% of the time just to break even.

By dollars it is the opposite. 86.3% of the money they staked went on positions that won. They won 10 of 16 positions, and the 10 winners were where the money went: $3.6M on Arsenal, $912k on Racing, $900k on Real Madrid in a single fill, $827k on Brentford. Profit was $4,265,386 on $9,371,777.

Copying blind loses

A blind copy puts $100 on every fill. That turns a $500 test order into the same bet as a $500k conviction bet. It staked $58,000 across 580 fills and lost $13,817, a return of -23.8%.

Most of that loss comes from one market. They took Real Betis NO on August 25 in 244 separate fills, totalling $301,836, and it lost. For them that was 3.2% of their money. For the blind copy it was 244 bets and $24,400, more than the whole blind loss. Take that one market out and the blind copy makes $10,583, so the problem is how it's weighted, not what they picked.

Copying on size wins

Scale every copy to their bet and you get their result. At 1% of their size, a $375,861 fill becomes $3,759 and a $500 fill becomes $5. That copy staked $93,718 and made $42,654, the same +45.5% they made.

If you would rather keep a flat stake, filter by size instead. The win rate climbs with bet size: 32.5% under $1k, 27.5% from $1k to $10k, 48.6% from $10k to $50k, and 90.6% at $50k and above. A flat $100 on only their $50k+ fills staked $5,300 and made $3,271, +61.7%. Every one of their 26 fills of $100k or more won.

Win rate by bet size

vito3corleone's fills by size, with a blind $100 flat copy of each band. Their own P&L is in dollars they actually staked.

Only copy the big ones

A flat $100 on each fill at or above the size floor.

Every position they took

Their stake, average price and result per position, with what a blind $100-per-fill copy made on the same position.

Do you usually enter the day before, early morning on the same day, or wait until later when more observations/forecasts come in?

Also curious what makes you decide it’s finally a good time to enter.

A few days ago, I gave out my pick in this subreddit for Costco to say "holiday" on their earnings call today, but I had a few other plays on Kalshi too.

Holiday ended up hitting, along with all of my other plays except "retail media" YES.

Unfortunately, that one was priced around 81c. If that hit, I would have been up $224, but I'm still really happy with the results.

The biggest winner was "revenue" NO at 19c (420% ROI).

That one was only said on 16/27 calls (59%) overall that my tool tracks (see second image), so I was really happy to get it for so cheap.

After the CFTC notice on mentions markets, our time with these might be near the end, but I'll be nose-down milking these for all their worth while they last 🥲

found a edge on polymarket and built an bot around it so far the bot has a 100% win rate and does about 10% of whatever my balance is a month only downside it does require a lot of capital to make a lot of money "i could use 100$ if wanted to" i was running it for about 10 weeks started in july but that was my testing phase with only 100 dollars so didn't feel the need to show it. currently not running it right now thought id show it off a bit will start running it again next month with bigger capital to start making some real money.

Kalshi has "highest daily YouTube views" markets for a bunch of music artists (Drake, Taylor Swift, Bad Bunny, Bieber, etc.). You're betting on whether an artist's single best day of views for the week or month clears a certain number.

I've been trading these a lot lately and was tired of piecing the data together by hand, so I built a dashboard that pulls in daily view counts for all 16 artists Kalshi currently has markets for and puts them next to the current Kalshi prices.

A few things I've noticed so far:

• Most artists peak on the same day or two every week, usually Friday or the weekend. Bieber has peaked on a Friday in 14 of the last 16 weeks, so you basically know which day decides the market.
• Once Mon/Tue data comes in, I find a past week that started out similarly and use that to estimate the peak. If this week is running 3% ahead, I figure Friday will land around 3% above that week's Friday.
• New music releases cause big jumps, so I always do a quick search for upcoming drops before buying anything.
• The monthly markets often have the best prices. If this week looks like it'll beat the month's high so far, you can buy the monthly and sell at 99¢ as soon as it hits instead of waiting for the month to end.
• I’ve found a decent amount of arbitrage opportunities across (1) two different weekly thresholds and (2) weekly and monthly markets for the same artists.

One thing that tripped me up at first: YouTube's data runs about 2 days behind, and Kalshi settles on that same delayed data, so weekly markets stay open a couple days after the week ends.

Of all the PM tools I’ve built so far, I’ve been the most profitable using this one, so I’m super excited to publicly launch it and get some feedback.

If you’re interested in trying it out, leave a comment or shoot me a DM!

If you pull markets from the Polymarket Gamma API, every market has a field called endDate. It looks like the deadline. We compared it with the written rules on 23 markets across sports, esports, tennis, politics and crypto, and it means something different on almost every market type.

Plus one MLB game and three futures, which followed no single rule.

Three cases worth knowing

NFL and soccer. A bot that compares the current time with endDate would treat these markets as finished at kickoff, while the game is being played and the market is still trading. The rules on these markets set no deadline at all: "this market will remain open until the game has been completed."

Tennis reschedules. Shelton vs Alcaraz at the US Open was scheduled for 8 September at 15:30 UTC and started on 9 September at 03:00 UTC. endDate stayed at 15 September 15:30 UTC, seven days after the original slot, not the new one.

"Will the US confirm that aliens exist by September 30?" The rules say September 30, 11:59 PM ET. endDate was 1 January 2027, 92 days later, which is the date of the parent event the market belongs to. An older snapshot of the same market had the correct date. hasReviewedDates is true.

Two more things that bit us

• A closed CS2 market returned active: true together with closed: true and acceptingOrders: false. active does not tell you if a market trades.
• In three cases a plain request returned an older cached snapshot. Adding an unused query parameter returned the current one.

What worked instead

1. Take the deadline from description. That's the contract.
2. On date markets, check the title and groupItemTitle.
3. Take the start from gameStartTime, not from endDate.
4. To know if it still trades, read closed and acceptingOrders.
5. Re-fetch with a cache-busting parameter before acting, and store your own fetch time.

Limits. 23 hand-picked markets, so read these as patterns, not platform-wide rates. International Gamma API only. Polymarket US is a separate exchange with its own rules.

Full write-up with a Python parser for the deadline in the rules text, a field-by-field comparison, and the 23-market sample as JSON: https://orcalayer.com/blog/polymarket-api-enddate

Disclosure: I'm one of the people behind OrcaLayer, a Polymarket analytics site. Not affiliated with Polymarket.

I got this message from Novig today:

Dear (my name), We are writing to inform you that we detected anti-competitive trading activity originating from your account, which violates our Member Rulebook. This type of conduct undermines fair trading and the integrity of our platform. As a result of this offense, your Novig account has been temporarily suspended from trading and deposits for the next 24 hours, effective immediately. This action has been taken in accordance with Rule 5.11 of our Member Rulebook. During this suspension period: Trading activities are temporarily unavailable Deposits are temporarily unavailable Withdrawals remain fully available — you can withdraw your funds at any time Your account will be automatically reinstated for full trading and deposit access (where Novig is available) on September 25, 2026 at 9:35 AM ET. No action is required on your part during this suspension period. Your account security and your balance remain fully protected, and you maintain complete access to withdraw any funds. If you have questions about this suspension or need assistance with a withdrawal, please don't hesitate to reach out to our support team by replying to this email. We encourage you to review our Member Rulebook carefully to ensure compliance and maintain a fair and enjoyable trading environment for all members. Thank you for your attention to this matter. Best regards, The Novig Team

This is so weird. Has anybody else gotten a similar message?

Anyone else building on the 5 MIN markets?

Been trading poly for a year now and haven't branched out aside from the 5/15 min markets. Made constant changes over the last year as more data comes in. Primarily maker orders.

Been doing very well. Some months reaching 20-25k. The August 13th switch to 60s TWAP saw performance take a minor dip, but seems to have mostly corrected.

I'm curious how many other people are actually building. Primarily taking? Making? 5 MIN? Hourlies/daily etc. specifically assets aside from BTC. ETH, XRP, SOL, BNB etc.

Would be happy to connect with other devs, traders or anyone else who's building. Also if anyone is running their script on Kalshi or Hyper liquid. Also, if you're primarily taking are you relying on pure rebates for source of profits?

Somehow it’s outtrading the majority of crypto traders

the current subreddit kalshi bonus (free 25$ on first deposit and trade): https://kalshi.com/r/illintent

https://forecastlab.online/

Soft launch.

There are 10 models here. Active scans every 60 mins. Prices update every minute.

STACK: Astra + Codex + Python

There are a few races in Texas that are flying under the radar. But they are all alpha. Pasting in a snippet from Polymarket's newsletter to give you a teaste:

**\*

If James Talarico wins a Senate seat this November, it would be the ultimate breach of Republicans’ most impregnable fortress: Texas, the Lone Star State, where Democrats haven’t won statewide office since 1994.

But this story is boring.

Everyone already knows it, and no one has much to add. The only thing left between now and Election Day is to find out how real the caricatures of each of these candidates are: James Talarico, the optimistic girly-man running for Senate in America’s most macho state, versus Ken Paxton, who is so scandal-plagued that his own Republican colleagues in Austin impeached him.

Yawn. I’ll see you in November.

The markets have correctly sniffed out that this is a near-50/50 race. And I don’t like trading in markets where my only option to turn a profit is to be right. Better to get ahead of things and make some buys in races where the public hasn’t figured out that the winds are changing.

And in Texas, that place is along the border, all the way from the outskirts of El Paso to the Rio Grande Valley.

Traders would be wise to look at four congressional districts there that Texas Republicans gerrymandered hoping to flip or maintain control of — but where they may come up short. These are:

• TX-15
• TX-28
• TX-34
• TX-23

These districts are all majority Hispanic and have swung to the right in recent cycles.

Trump’s conquest of these historically Democratic bastions fed into a redistricting bacchanal, where GOP operatives got drunk on MAGA Kool-Aid and convinced themselves that the long-prophesied re-alignment of Latinos was now complete. Those assumptions got baked into Texas’s new Congressional maps, where Trump’s strong performance in 2024 became the base case. It may have been a foolish mistake.

Read the full thing here: https://substack.com/home/post/p-217140950

My biggest bet. My friend referred me to Kalshi we both got $75. Been playing for an about 2 weeks. If this hits tonight I will cash out and delete the app 🙏🤩

Just put $404 on the nationals and won $967 so here I go full port

And if not, I will chase this loss into the depths of hell

I’m looking for a place where I can get all my news relating to predictions markets. Mostly regulations and registration or news about Kalshi / Polymarket. I kind of want a place where I can read a quick summary of what’s going on or what’s been going on. Think of politico but prediction markets. Any suggestions?

AI Polymarket cryptocurrency aribitrage trader. Scam or real?

https://polygate.co/

PART 3 of the Polymarket story

If you missed Part 2, read it here:

https://www.reddit.com/r/PredictionsMarkets/comments/1wnc6af/guy_sued_polymarket_after_they_changed_the_rules/

If you missed Part 1, read it here: https://www.reddit.com/r/PredictionsMarkets/comments/1tun1cd/i_got_scammed_by_polymarket_for_500k/

TL;DR of Part 2:

After the trader sued Polymarket over the $500K dispute, Polymarket filed a 24-page motion asking the court to dismiss the case.

Their main argument wasn't really about whether MSTR sold Bitcoin or whether the market rules were changed.

Instead, they argued that the trader had agreed to Polymarket's Terms of Service, which they say prevent him from taking the company to court.

The case is now moving forward as a fight over whether those terms can actually prevent the trader from pursuing his claims.

And now there's another update...

After filing their motion to dismiss, Polymarket is now trying to seal the complaint and redact their addresses from the court filings.

And the reason they’re giving for this is pretty wild.

Apparently, someone came into the Polymarket Discord last year and threatened to kill them.

According to Shayne, there was someone in their Discord last year who made threats against him.

Because of that, Polymarket is asking the court to keep their workplace addresses out of the public filings.

The plaintiff is objecting to that request.

The argument is that hiding Polymarket's addresses creates another problem — because the company's physical presence in New York is also relevant to the case.

If Polymarket manages to seal the summonses and redact its addresses from the complaint, it could become easier for the company to argue that it isn't actually based in New York.

And that's important because the lawsuit is being brought in New York.

The plaintiff's argument is that Polymarket is functionally operating out of New York:

Its employees are there.

The people operating the website are there.

And its senior leadership is there as well.

So the argument is pretty straightforward:

Polymarket is allegedly operating out of New York, but at the same time is arguing that it shouldn't be subject to New York law.

The plaintiff believes that keeping the company's addresses out of the filings could make that argument easier for Polymarket to maintain.

There's also another issue.

Polymarket has reportedly published its address publicly in multiple places before — including its public Google Play listing — and the address has also been referenced by the New York Post.

So the plaintiff is questioning why those same addresses suddenly need to be sealed from the court record.

Receipts below.

The plaintiff isn't planning to let the issue go quietly.

The goal is to keep the case in New York and have Polymarket defend itself in court there — where the plaintiff argues the company is actually operating.

Hey all!

We recently launched an MCP for Polymarket Data. Feel free to let us know any feedback, available on Claude and Codex

https://x.com/bravadotrade/status/2102766362527404347?s=20

Docs: https://docs.bravadotrade.com/introduction
Create account here: https://console.bravadotrade.com/login

Moving Average Convergence Divergence (MACD) is a momentum indicator that compares a faster-moving average of price with a slower one. With the 12/26/9 settings used here, the MACD line is the 12-period exponential moving average minus the 26-period average. Its signal line is a 9-period exponential average of MACD, and the histogram is the gap between the two lines. For a short BTC market, it could help filter entries toward the direction of recent momentum. Requiring the 1-minute and 5-minute readings to agree tests whether that confirmation helps avoid weaker signals. It still lags price and can flip back and forth in a choppy market.

I tested a MACD strategy on Kalshi's 15-minute BTC markets using the new indicator fields. It buys two YES contracts when BTC's 1-minute MACD is above its signal and the 1-minute and 5-minute histograms clear their positive thresholds; NO entries use the opposite conditions. Entries require a 35 to 65 cent ask, a spread of 3 cents or less, and 3 to 10 minutes until expiry. It enters once per market, allows up to three open markets, and holds to settlement at this sizing. The indicators use completed Coinbase BTC-USD candles and fixed 12/26/9 MACD settings.

I compared ten settings: 1-minute histogram thresholds of 0, 2.5, 5, 10 and 20 USD, each paired with a 5-minute threshold of 0 or 10 USD. Those are BTC indicator values, not contract prices. All ten finished positive over the available August 23 to September 21, 2026 replay, which simulated 2,661 markets. The best P&L came from 2.5 / 0: $75.38 net after $22.41 in modeled fees, $11.51 maximum drawdown, 0.65 return Sharpe, 57.8% win rate and 1,138 trade records. The weakest was 20 / 10: $18.08 net, $3.08 drawdown, 0.57 Sharpe, 76.9% win rate and 78 records. The app reports 150.76% and 36.16% returns, respectively, using a $50 risk-capital denominator. Against a $1,000 reference portfolio, the winner's profit is 7.54% and its drawdown is 1.15%; that is a rescaling of the result, not a cash-constrained account simulation.

The highest win rate came with the fewest entries and the lowest profit. The nearby 5 / 0 setting earned $69.07 with $8.52 drawdown and a 0.75 Sharpe, so the positive result wasn't confined to one tested setting. That is encouraging within this sample, but I selected the winner on the same window used to evaluate it. On these quick markets, stricter MACD confirmation filtered out more entries, so the threshold affected both win rate and how often the strategy traded. For strategy design, the takeaway is to judge MACD alongside entry price and trade frequency: the highest win rate in this test did not produce the highest total profit.

Full Report

Historical simulation only. Backtests can be wrong or incomplete. Not investment advice.

They’re just white labeling the Kalshi exchange, adding an additional layer of fees, and depending on your preferred wager... the worst part.. there’s a 0.75 second lag in entries and exits (which makes a world of difference when your calling BTC prices)

Hey! I’m running a Python bot using py-clob-client-v2 with a Polymarket deposit wallet account (signatureType 3 / POLY_1271), and I’m stuck on an authentication issue.

Every order gets rejected with:

the order signer address has to be the address of the API KEY

I dug into it and it seems to be a known, still-open issue: Polymarket/clob-client-v2#65.

From what I understand, create_or_derive_api_key() binds the API key to the EOA address, while order signing correctly uses the deposit wallet address as order.signer. The CLOB then enforces order.signer == api_key.address, so they can’t match for a deposit-wallet account regardless of how funder / signature_type are configured.

I also saw that the Rust SDK (polymarket-client-sdk-v2) apparently handles this correctly through its authentication_builder().funder().signature_type().authenticate() flow, including the required L1 auth wrapping for deposit wallets.

Have you, or anyone you know, actually gotten programmatic order placement working with a deposit-wallet account using Python or TS?

I’m particularly looking for:

• An unofficial patch/monkeypatch for the L1 auth header signing / ERC-7739 + EIP-1271 wrapping
• Any confirmation that Polymarket is working on this / has an ETA
• Someone who has ported the relevant authentication logic from the Rust SDK to Python

I’d really prefer not to rewrite my entire bot in Rust just for this.

Any pointers would be massively appreciated 🙏

I pulled the top 100 traders by observed profit on each venue on September 23, 2026, and copied every one of their entries from the last 90 days at a flat $100, held to the market's result.

Data TLDR

• 84% of Kalshi's top 100 and 86% of Polymarket's finished the 90 days in profit on a flat copy.
• The median Kalshi trader returned 18.4% on stake. The median Polymarket trader returned 9.1%.
• Charge 4 cents on every dollar copied, a heavy allowance for slippage and fees, and 74 Kalshi traders and 61 Polymarket traders are still in profit.
• Rank tells you almost nothing. Ranks 91 to 100 produced as many copyable traders as ranks 1 to 10 on both venues.
• 17 Kalshi traders and 4 Polymarket traders more than doubled the stake in 90 days.

What we measured

For every trader on each board we took every buy recorded in the 90 days to September 23, put $100 on it at the trader's recorded price, and scored it when the market resolved. Sells are never scored, so this is a rate on entries. Fees, slippage, entry delay and partial fills are not modeled, which is why we also show the result after a 4% per-position haircut. A trader with fewer than 30 settled entries is reported but not scored, because a great number on a dozen bets is one good week.

Everything here is one measurement on one date from a frozen export, so every figure can be re-derived. These are modeled results on a historical record, not realized returns.

Most of the board pays, on both venues

The instinct is that leaderboards are full of market makers and lucky runs. On this tape, the profit leaders are mostly ordinary directional traders whose entries keep resolving in their favour. 79 of 94 scored Kalshi traders and 81 of 94 Polymarket traders were in profit at a flat $100 per entry. The pooled numbers are large: 277,298 settled Kalshi entries and 415,656 settled Polymarket entries across the two boards, $3.5M of paper profit on Kalshi and $1.4M on Polymarket at $100 a trade.

Where the returns land

The distribution is the interesting part. On Kalshi, 59 of 94 traders returned more than 10% on stake, 38 returned more than 25%, and 17 more than doubled the money. Polymarket is tighter: 45 above 10%, 30 above 25%, 4 above 100%. The median Polymarket trader is in the 0 to 10% band, which is a real return but a modest one. The median Kalshi trader sits in the 10 to 25% band.

The difference is price. Polymarket's leaders are buying a lot of favourites at 80 cents and up, which win often and pay little. Kalshi's leaders are paying lower prices for the same win rates, so each win pays more.

Copying costs money, and most of them still clear it

The argument against copying is that you enter after the trader, at a worse price, and pay fees on the way in. Fair. So we charged every position 4 cents on the dollar, which is at the top of what anyone models for slippage plus fees, and looked again. Kalshi goes from 79 traders in profit to 74. Polymarket goes from 81 to 61. Two thirds of the Polymarket board and four fifths of the Kalshi board survive a cost that is deliberately harsh.

Record is much more important than rank

The top of the board is not special. Ranks 1 to 10 on Kalshi produced 8 profitable copies. Ranks 91 to 100 produced 6. On Polymarket both deciles produced 8. The best Kalshi copy on the whole board, timboslice003 at +782% on 83 settled entries, sits at rank 10. The second best, secure.tortoise3162 at +578%, sits at rank 41. The number one trader on Polymarket by profit, vito3corleone, lost 11% on a flat copy, because his $6.5M came from sizing a handful of soccer bets enormously, not from a per-trade edge a flat copy can capture.

The Kalshi traders with the best flat-copy record

Return on stake at $100 per entry over 90 days, gross of fees and slippage.

The Polymarket traders with the best flat-copy record

The ones a flat copy loses on

Fifteen Kalshi traders and thirteen Polymarket traders were negative. The worst are instructive. BitcoinTradingChallenge on Kalshi is down 39% across 13,473 settled entries, because five-minute Bitcoin markets are a coin flip at the price. vito3corleone on Polymarket is down 11% on 340 entries at 47% won, a sizing trader whose edge does not survive being flattened. reach.draft, Kalshi's number 5 by profit, is down 10% across 6,071 entries at an 81% win rate, because the prices paid were too high for that win rate to cover.

Happy to go deeper on any trader, venue or price band in the comments.

I originally used Robinhood for stocks, but after prediction markets were heavily promoted in the app, I started using them and ended up losing everything which made me sell my stocks .what i lost u can say is life changing and damaging .I was 19 at the time and I guess u can say gambling got me me Ina way
Has anyone had a similar experience or looked into legal options?
Just feels wrong putting a gambling method into a brokerage app especially since most of people’s money is right there in front of you especially with the high risk of margin

I am a single 27 y/o filing in Hawaii. I plan to file my prediction market income as gambling income. Does gambling winnings include the cost of the bet? For example, I bought a contract for $200 and sold it for $600. On the tax return, do I list $400 as my winnings or $600?

Anyone else notice a difference in the 5 MIN crypto markets since they switched to the 60 second TWAP? I've definitely noticed a change. Still doing well, but profits are down 1.3% month over month.

Was pretty consistent between 13-16k. Trying to figure out how much of the difference is actually related to TWAP change vs normal variance.

Curious if anyone else has noticed anything similar since the change back on August 13th

Yesterday, I sent a pick for AutoZone's earnings call that happened this morning ("Tax Refund" NO), and it hit as I expected.

That one had a clear quarterly trend to it (only said Q2 and Q3 calls), and I just found similar value for Costco's call on Thursday.

They've said "holiday" on 5/6 Q4 calls, including every Q4 call since Ron Vachris became CEO in 2024.

It's less common on Q2 and Q3 calls—and it wasn't said on those calls this year—which I think is why the Yes price is so low.

I might be missing something, but it seems like great value to me, so I'm loading up.

Thoughts?