投注公司通过“限额”压低赢家下注额度，例如2018年某英国博彩公司把NBA常规赛MVP的冠军下注上限降到£5（$6.50）。监管数据显示，英国过去一年活跃账户中有4.3%的“stake factor”低于100%，而马萨诸塞州仅0.64%账户被限制；在赔率内含利润率低至4.5%的情况下，玩家画像可把利润率再提高10–20%，而单个“鲸鱼”甚至可使PointsBet在新泽西线上体育投注收入份额于2024年3月从11%升至24%。

画像会在下注前后同时打分：设备（手机优于电脑）、入金方式（借记卡对比电商钱包）、性别（女性更少见却更可疑）等都会改变风险判断。行业人士称首注后就能以80–90%的把握判断账户终身价值；若前10注的“closing-line value”持续领先市场往往会被迅速限额，内部系统还会每6–8小时复核风险分数，并重点审查电商钱包用户、女性与单笔超过€100（$115）的下注，把可疑者降到30% stake factor、确认者降到1%（DraftKings在2023年把Felix Baum当作高额VIP后也几乎清零其额度）。

被限制后，“代理下注”与“养号”成为规模化手段但风险与成本可量化：Caesars曾在去年因重复机台串关作废Thomas McPeek的$800,000奖金；职业“mover”网络把“stiffing”视为3–5%的经营成本，低端抽走10–20%利润且不承担亏损，而有人声称拥有35个活跃“beard”。小型书商也用数据执法：2023年上线、约50,000账户的AK Bets一周踢出13人（含有人试图在进球后以£400抢慢数据联赛），而各地反制从澳大利亚赛马/赛狗常见A$2,000（$1,300）最低可赢额度、到西班牙大量诉讼、再到纽约州议员Alex Bores于9月26日提交禁止账户限额法案不等。

Sportsbooks use stake restrictions to cap winners, such as a 2018 case where an NBA MVP wager was limited to £5 ($6.50). Regulators report 4.3% of active UK accounts had stake factors below 100% versus 0.64% limited in Massachusetts; with embedded margins as low as 4.5%, profiling can lift margins by 10–20%, and one “whale” helped PointsBet’s New Jersey online revenue share jump from 11% to 24% in March 2024.

Profiling scores customers before and after the first bet using signals like device (phone vs computer), funding method (debit vs e-wallet), and even gender (women are rarer, so “suspicious”). Consultants claim sportsbooks are 80–90% sure of an account’s lifetime value after the first bet; strong closing-line value over the first ten wagers often triggers limits, with internal systems rechecking risk scores every 6–8 hours and flagging e-wallet users, women, and bets over €100 ($115), cutting suspected sharps to 30% stake factor and confirmed ones to 1% (as seen when DraftKings’ 2023 VIP treatment of Felix Baum was reversed).

Once limited, sharps scale via proxies and “priming,” but the economics include cancellations and leakage: Caesars voided $800,000 in winnings for repeated parlay play, “stiffing” is estimated at 3–5%, and lower-end movers take 10–20% of winnings while avoiding losses, with one claiming 35 active beards. Enforcement is data-driven even at small books—AK Bets (launched 2023, ~50,000 accounts) expelled 13 users in a week, including a £400 attempt after a goal—while policy responses range from Australia’s common A$2,000 ($1,300) minimum-win rules to Spanish court wins and a New York bill filed on September 26 to ban limits.

Source: The battle to stop clever people betting

Subtitle: The tools bookmakers use to block data-savvy gamblers, and how to get round them

Dateline: 12月 18, 2025 05:43 上午 | Dublin and Las Vegas