[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"doc-detail-86244-en":3,"doc-seo-86244-105":29,"detail-sidebar-cat-0-en-105":91},{"code":4,"msg":5,"data":6},0,"success",{"doc_id":7,"user_id":8,"nickname":9,"user_avatar":10,"doc_module":4,"category_id":11,"category_name":12,"doc_title":13,"doc_description":14,"doc_content":15,"file_id":16,"file_url":17,"file_type":18,"file_size":19,"view_count":20,"is_deleted":4,"is_public":20,"is_downloadable":20,"audit_status":20,"page_count":21,"language":22,"language_code":23,"site_id":24,"html_lang":23,"table_of_contents":25,"faqs":26,"seo_title":13,"seo_description":14,"update_tm":27,"read_time":28},86244,1374391974585,"Genevieve","https://ap-avatar.wpscdn.com/davatar_276721f389ce27ea32af1340a28f341c",8,"Research & Report","Time Is Money Incentivized Causal Transaction Ordering","Front-running undermines blockchains by letting attackers observe functional user transactions and publish competing ones earlier to capture rewards, weakening user incentives and reducing market efficiency. The core goal is enforcing causality—ordering txA before txB whenever the attacker learned txA before publishing txB—but causality is only visible to the attacker and reward sizes vary widely. PRECEDE introduces an incentive-compatible transaction ordering mechanism that removes the economic benefit of front-running using a power-weighted randomized lottery, and it also blocks sandwich attacks.","Time Is Money: Incentivized Causal Transaction Ordering  \nHongyin Chen  \nTechnion  \n[hongyin.chen.contact@gmail.com](hongyin.chen.contact@gmail.com)  \nXu Zheng  \nMiami Herbert Business School [zhengxu@miami.edu](zhengxu@miami.edu)  \nJichen Li  \nTsinghua University [jichenli@mail.tsinghua.edu.cn](jichenli@mail.tsinghua.edu.cn)  \nIttay Eyal  \nTechnion[ittay@technion.ac.il](ittay@technion.ac.il)  \narXiv :2607 . 1 1496v 1 [ cs .CR] 13 Jul 2026  \nAbstract—Front-running is a subtle and persistent problem for blockchains. A blockchain is a stateful virtual machine executing instructions called transactions. Users earn rewards by publishing functional transactions essential to the system. Attackers observe these transactions and publish their own ahead of the users’, seizing the reward and eroding users’incentive to publish functional transactions. Preventing frontrunning means enforcing causality: If an attacker receives transaction txA and then publishes transaction txB , then txA must be ordered before txB . However, this causality is only observed by the attacker. Practical systems order transactions by bid amount, so transactions willing to pay more get executed first, but this only results in a bidding war eroding users’rewards. Though numerous ordering approaches have been proposed, none achieves causality, leaving users vulnerable to front-running.  \nWe present PRECEDE, a mechanism-design approach that enforces transaction causality by removing the economic incentive to front-run. PRECEDE orders transactions by a powerweighted randomized lottery, whose winning probability grows super-linearly in the bid. The user’s strategy of publishing a transaction with a deterring bid forms an equilibrium where the attacker refrains from competing. Moreover, PRECEDE prevents the prominent sandwich attack, which relies on front-running. PRECEDE can be directly deployed in any censorship-resistant blockchain with a simple change to its transaction ordering mechanism.  \n1. Introduction  \nBlockchains underpin the $3 trillion cryptocurrency market [1] and the $170 billion Decentralized Finance (DeFi) market [2] . A blockchain is a stateful virtual machine that executes an ordered sequence of instructions called transactions, each of which updates the machine’s state. Blockchain validators [3], [4], [5] extend this sequence by appending vectors of transactions called blocks. Users issue many functional transactions that benefit the system, such as arbitrage that aligns prices across markets [6], among others [7], [8] . They receive rewards from the system for these transactions.  \nThese rewards, however, are exposed to frontrunning [9] . When a user publishes a functional transaction, it is publicly visible before a validator places it on chain. An  \nattacker observes it and can bribe the validator to order her own transaction ahead of the user’s, seizing the reward [9],[10] . Front-running also serves as a building block for other order-manipulation attacks [11], [12], [13] . Practical chains often order transactions by bid [3], [5], [14], turning frontrunning into a race to the bottom: On Flashbots [15], for instance, arbitrage winners pay validators a median of over 90% of their reward [16] . Front-running is therefore harmful to blockchain functionality: With their rewards competed away, users have little incentive to issue functional transactions, and the markets that rely on them lose efficiency [6] .  \nAn extensive body of work (§2) addresses these attacks by limiting the validators’ ability to manipulate transaction order. One approach is to order transactions by their arrival times at an ordering committee [17],[18],[19],[20], but this fails to prevent front-running [21]: No such protocol ensures ordering an earlier transaction ahead of a later one [17],[19] . A second approach makes the order within each block random [22], [23] . However, an attacker can publish many copies so that one likely precedes the target [24], [25]; such spam b","cbCaioJgd2IOvnOs","https://ap.wps.com/l/cbCaioJgd2IOvnOs","pdf",455503,1,28,"English","en",105,"# Abstract\n# Introduction","[{\"question\":\"What problem does the paper address in blockchain transaction ordering?\",\"answer\":\"The paper addresses front-running, where attackers observe a functional user transaction and publish their own transaction earlier to capture the reward and erode the user’s incentive to submit functional transactions.\"},{\"question\":\"How does PRECEDE enforce causality in transaction ordering?\",\"answer\":\"PRECEDE enforces transaction causality by removing the economic incentive to front-run. It orders transactions using a power-weighted randomized lottery whose winning probability grows super-linearly with the bid.\"},{\"question\":\"What additional attack does PRECEDE aim to prevent?\",\"answer\":\"PRECEDE prevents the sandwich attack, which relies on front-running to manipulate transaction ordering and capture value.\"}]",1784209748,71,{"code":4,"msg":30,"data":31},"ok",{"site_id":24,"language":23,"slug":32,"title":13,"keywords":33,"description":14,"schema_data":34,"social_meta":86,"head_meta":88,"extra_data":90,"updated_unix":27},"time-is-money-incentivized-causal-transaction-ordering","",{"@graph":35,"@context":85},[36,53,68],{"@type":37,"itemListElement":38},"BreadcrumbList",[39,43,47,50],{"item":40,"name":41,"@type":42,"position":20},"https://docshare.wps.com","Home","ListItem",{"item":44,"name":45,"@type":42,"position":46},"https://docshare.wps.com/document/","Document",2,{"item":48,"name":12,"@type":42,"position":49},"https://docshare.wps.com/document/research-report/",3,{"item":51,"name":13,"@type":42,"position":52},"https://docshare.wps.com/document/time-is-money-incentivized-causal-transaction-ordering/86244/",4,{"url":51,"name":13,"@type":54,"author":55,"headline":13,"publisher":57,"fileFormat":60,"inLanguage":23,"description":14,"dateModified":61,"datePublished":62,"encodingFormat":60,"isAccessibleForFree":63,"interactionStatistic":64},"DigitalDocument",{"name":9,"@type":56},"Person",{"url":40,"name":58,"@type":59},"DocShare","Organization","application/pdf","2026-07-17","2026-07-16",true,{"@type":65,"interactionType":66,"userInteractionCount":20},"InteractionCounter",{"@type":67},"ViewAction",{"@type":69,"mainEntity":70},"FAQPage",[71,77,81],{"name":72,"@type":73,"acceptedAnswer":74},"What problem does the paper address in blockchain transaction ordering?","Question",{"text":75,"@type":76},"The paper addresses front-running, where attackers observe a functional user transaction and publish their own transaction earlier to capture the reward and erode the user’s incentive to submit functional transactions.","Answer",{"name":78,"@type":73,"acceptedAnswer":79},"How does PRECEDE enforce causality in transaction ordering?",{"text":80,"@type":76},"PRECEDE enforces transaction causality by removing the economic incentive to front-run. It orders transactions using a power-weighted randomized lottery whose winning probability grows super-linearly with the bid.",{"name":82,"@type":73,"acceptedAnswer":83},"What additional attack does PRECEDE aim to prevent?",{"text":84,"@type":76},"PRECEDE prevents the sandwich attack, which relies on front-running to manipulate transaction ordering and capture value.","https://schema.org",{"og:url":51,"og:type":87,"og:title":13,"og:site_name":58,"og:description":14},"article",{"robots":89,"canonical":51},"index,follow",{"doc_id":7,"site_id":24},{"code":4,"msg":5,"data":92},[93,97,101,105,110,115,120,123,128,131,135],{"id":20,"doc_module":4,"doc_module_name":45,"category_name":94,"show_sort_weight":95,"slug":96},"Story & Novel",90,"story-novel",{"id":46,"doc_module":4,"doc_module_name":45,"category_name":98,"show_sort_weight":99,"slug":100},"Literature",80,"literature",{"id":52,"doc_module":4,"doc_module_name":45,"category_name":102,"show_sort_weight":103,"slug":104},"Exam",70,"exam",{"id":106,"doc_module":4,"doc_module_name":45,"category_name":107,"show_sort_weight":108,"slug":109},5,"Comic",60,"comic",{"id":111,"doc_module":4,"doc_module_name":45,"category_name":112,"show_sort_weight":113,"slug":114},6,"Technology",50,"technology",{"id":116,"doc_module":4,"doc_module_name":45,"category_name":117,"show_sort_weight":118,"slug":119},7,"Healthcare",40,"healthcare",{"id":11,"doc_module":4,"doc_module_name":45,"category_name":12,"show_sort_weight":121,"slug":122},30,"research-report",{"id":124,"doc_module":4,"doc_module_name":45,"category_name":125,"show_sort_weight":126,"slug":127},9,"Religion & Spirituality",20,"religion-spirituality",{"id":126,"doc_module":4,"doc_module_name":45,"category_name":129,"show_sort_weight":126,"slug":130},"World Cup","world-cup",{"id":132,"doc_module":4,"doc_module_name":45,"category_name":133,"show_sort_weight":132,"slug":134},10,"Lifestyle","lifestyle",{"id":136,"doc_module":4,"doc_module_name":45,"category_name":137,"show_sort_weight":106,"slug":138},19,"General","general"]