11affiliationtext: Technical University of Munich, Garching,
Germany22affiliationtext: Flashbots, San Francisco, CA, USA33affiliationtext:
Ethereum Foundation, Lisbon, Portugal

# Who Wins Ethereum Block Building Auctions and Why?

Burak Öz  Danning Sui  Thomas Thiery  Florian Matthes

###### Abstract

The MEV-Boost block auction contributes approximately $90\text{\,}\%$ of all
Ethereum blocks. Between October 2023 and March 2024, only three builders
produced $80\text{\,}\%$ of them, highlighting the concentration of power
within the block builder market. To foster competition and preserve Ethereum’s
decentralized ethos and censorship-resistance properties, understanding the
dominant players’ competitive edges is essential.

In this paper, we identify features that play a significant role in builders’
ability to win blocks and earn profits by conducting a comprehensive empirical
analysis of MEV-Boost auctions over a six-month period. We reveal that block
market share positively correlates with order flow diversity, while
profitability correlates with access to order flow from Exclusive Providers,
such as integrated searchers and external providers with exclusivity deals.
Additionally, we show a positive correlation between market share and profit
margin among the top ten builders, with features such as exclusive signal,
non-atomic arbitrages, and Telegram bot flow strongly correlating with both
metrics. This highlights a “chicken-and-egg” problem where builders need
differentiated order flow to profit, but only receive such flow if they have a
significant market share. Overall, this work provides an in-depth analysis of
the key features driving the builder market towards centralization and offers
valuable insights for designing further iterations of Ethereum block auctions,
preserving Ethereum’s censorship resistance properties.

##  1 Introduction

Ethereum blockchain grows by one block every 12 seconds if the block proposal
slot is not missed. The consensus specifications [48] expect the selected
consensus participant, the validator, to build a block and propose it to the
rest of the network. However, nearly $90\text{\,}\%$ [84] of all new blocks
are produced via the MEV-Boost[21] block building auction, which is a
Proposer-Builder Separation (PBS) [35] implementation. In this mechanism, the
proposer acts as an auctioneer, selling their block building rights, while a
set of out-of-protocol entities, referred to as builders, compete by sending
bids to intermediaries known as relays. The proposed MEV-Boost block is signed
by the respective proposer, while the payload is constructed by the winning
builder. By separating block proposing and building tasks, MEV-Boost aims to
avoid validator centralization caused by the sophistication of running complex
strategies to extract Maximal Extractable Value (MEV) [59].

As an out-of-protocol instantiation of PBS, MEV-Boost preserves
decentralization on the consensus layer as validators have uniform access to
MEV rewards [55]. However, it concentrates power within the builder market due
to economies of scale. Between October 2023 and March 2024, only three
builders, beaverbuild, rsync, and Titan, produced approximately
$80\text{\,}\%$ of all MEV-Boost blocks. With a small set of builders creating
Ethereum blocks, the network becomes vulnerable to censorship [61, 81, 83].

To preserve Ethereum’s decentralized ethos and censorship resistance
properties, fostering competition in the MEV-Boost block building auction is
essential. As a first step, we must understand the competitive edges of the
dominant players. MEV-Boost block builders currently have varying
profitability levels, which do not strictly increase with the block market
share they own, as shown in Figure 1. Thus, we need to study the critical
factors for both obtaining market share and earning profits. Recent work [88]
highlighted the pivotal role certain order flow providers play in winning
blocks. We extend their insights by analyzing all active builders, order flow
over time, and specific strategies to provide a comprehensive understanding of
what drives builders’ success in the MEV-Boost auction.

Our contributions can be summarized as follows:

  * •

We develop a novel methodology to identify key features in MEV-Boost builders’
success in winning blocks and earning profits, and provide metrics to monitor
the builder market.

  * •

We reveal that builders’ block market share positively correlates with order
flow diversity, while profitability correlates with access to order flow from
Exclusive Providers (EPs), such as integrated searchers and external providers
with exclusivity deals.

  * •

We show a positive correlation between market share and profit margin among
the top ten builders, with features such as exclusive signal, non-atomic
arbitrages, and Telegram bot flow strongly correlating with both metrics.

  * •

We highlight a “chicken-and-egg” problem where builders need differentiated
order flow to profit, but only receive such flow if they have a significant
market share.

  * •

We discuss the implications of our findings for Ethereum block auctions and
explore existing solutions for addressing the censorship threat posed by the
currently centralized block builder market.

Figure 1: Bubble plot illustrating MEV-Boost builders’ profit margin (average
block value kept by the builder) on the x-axis and total profit in ETH on the
y-axis. Bubble size represents the builder’s market share, measured by the
total number of blocks built. Color indicates profitability, with a
$15\text{\,}\%$ profit margin threshold distinguishing high-profit margin
builders. Builders with less than $0.01\text{\,}\%$ market share or a profit
margin below $-50\text{\,}\%$ are omitted for brevity.

##  2 Background and Related Work

In this section, we present the necessary background and discuss the related
work.

###  2.1 Proposer-Builder Separation and the MEV-Boost Block Auction

The PBS framework [47] introduces the decoupling of block building and
proposal tasks for staked Ethereum validators. While the validator remains
responsible for signing and proposing the block, the new builder role handles
the block content (i.e., execution payload) preparation. By delegating the MEV
extraction task to builders, PBS aims to lower the barrier for entry for
validators, who no longer need to become proficient in block building.

Achieving the PBS goal is essential for Ethereum’s consensus security [55].
However, it is challenging due to the difficulty of establishing a fair
exchange of value between the validator and the builder [19]. Validators need
assurance of payment and execution payload delivery by the builder, while
builders must ensure their block content is protected against unbundling and
is included on-chain. Although solutions to fair exchange problem have been
discussed [43, 15], there is no enshrined PBS implementation in the Ethereum
protocol.

Flashbots proposed an out-of-protocol PBS implementation, MEV-Boost[21], which
introduces relay intermediaries to address the fair exchange issue. This
implementation became active with the Merge [28] in September 2022. In MEV-
Boost, relays receive blocks from builders and validate111Optimistic relays
[33] such as Ultra Sound Relay[41] are an exception. These relays can make the
builder bids available to the proposer without validation since they have
additional security mechanisms in place (e.g., collateralized builder funds).
them to ensure that the promised bid to the validator is paid and that the
block is valid to become canonical. To protect builders against unbundling
attacks, relays follow a commit-and-reveal scheme, disclosing only the block
header when retrieving the proposer’s signature. Although MEV-Boost requires
trust in third parties, relays are presumed to act honestly due to their
reputations. However, there have been instances where proposers exploited
relay vulnerabilities to unpack and steal valuable MEV bundles from searchers
[39, 16], indicating that the fair exchange problem remains unresolved.

An MEV-Boost block auction round [50] follows the
$12\text{\,}\mathrm{-}$second slot structure of the Ethereum consensus
protocol [48]. To win the right to produce the block proposed at slot $n$,
builders start competing at slot $n-1$ by sending bids to the relays. Over
time, builders increase the value of their bids, derived from the fees offered
by users sending transactions to the public mempool and Exclusive Order Flow
(EOF) providers (e.g., MEV searchers, Telegram bots [40, 27]) submitting
valuable bundles and transactions to the builders’ private Remote Procedure
Call (RPC) endpoints. Relays validate the builder bids and make them available
to the proposer, who can continuously poll the getHeader endpoint on the mev-
boost middleware to receive the highest bid from every registered relay.
Eventually, the validator blindly signs the accepted bid’s block header and
submits it to the winner relay, who publishes the full block to the network.
The described MEV-Boost process is summarized in Figure 2.

###  2.2 Maximal Extractable Value

MEV refers to the sum of value extractable from a blockchain in any given
state, through transaction ordering, insertion, and exclusion [59]. Using
these techniques and analyzing the blockchain and network state, MEV
searchers, running bots and sophisticated smart contracts,222Example MEV bot
contract: 0x6980a47bee930a4584b09ee79ebe46484fbdbdd0 execute strategies such
as Decentralized Exchange (DEX)-DEX or Centralized Exchange (CEX)-DEX
arbitrages, sandwiches, and liquidations to earn profits [73, 64].

Due to the competitive, time-sensitive,333Arbitrages between an off-chain CEX
and an on-chain DEX or two DEXes on different blockchains can be considered
time sensitive as execution is non-atomic. and state-dependent nature of MEV
extraction, searchers must pay fees like bribes to builders for prioritized
inclusion and execution in blocks. As a result, builders earn a proportion of
the MEV that the searchers extract. However, they must also share their
earnings with the proposers to win the MEV-Boost block auction, as described
previously (see Section 2.1). Thus, MEV, originating from benign user
transactions altering the blockchain state, flows through various entities in
the block production pipeline and provides economic incentives for
participants throughout the supply chain.

###  2.3 Order Flow Auctions

Order Flow Auctions (OFAs) are auctions where users share trade orders as
unsigned transactions with searchers who compete in a sealed-bid format to
backrun them. Users are incentivized by refunds up to $90\text{\,}\%$ of the
value bidders extract from backrunning opportunities [29], along with frontrun
protection. OFAs, such as MEVBlocker [29] and MEV-Share [52], provide an RPC
endpoint for users to privately submit transactions instead of sending them to
the public mempool. These transactions are braodcasted, either in full detail
or selectively, to bidders who compete to submit the highest value bundle to
block builders. Builders then refund OFA users using the fee from the winning
searcher’s bundle.

###  2.4 Related Work

Previous work has focused on Ethereum block building auctions from
theoretical, game-theoretic, and empirical standpoints. [6] reveals that
searchers prefer submitting bundles to builders with high-market share, and
new entrants need to subsidize to obtain market share unless they operate
their own searchers. [14] conducts an empirical study examining the strategic
behavior of MEV-Boost block builders, focusing on their bidding behavior and
order flow strategies, and establishes core metrics for analyzing builder
profiles and identifying their competitive edges. [87] provides a game-
theoretic model of the MEV-Boost auction and adopts an agent-based model to
simulate builder strategies, showing the importance of latency and access to
order flow. [88] identifies pivotal order flow providers for block builders
and measures the competition and efficiency of the MEV-Boost auctions. [62]
shows that integrated High-Frequency Trading (HFT) builders who extract top
block position opportunities, such as CEX-DEX arbitrages, are favored to win
the block auction when price volatility increases. [64] introduces heuristics
tailored to detect CEX-DEX arbitrages, confirming that price volatility and
the arbitrage volume are correlated. The work provides empirical evidence that
certain builders, such as beaverbuild and rsync, run their own searchers to
extract this value. [55] proves the necessity of a competitive PBS auction to
enable homogeneous proposer rewards and avoid concentration of stake among
validators proficient in extracting MEV rewards. Block proposal timing games
have been studied in [74, 89], showing the marginal value of time for
validators to earn more rewards from the builder bids. [82] measures the MEV-
Boost market concerning the entities involved in the block production
pipeline, and [65] analyzes the Ethereum landscape with a comparison between
PBS and non-PBS blocks.

Figure 2: MEV-Boost block production process. Users (blue) submit transactions
to the public mempool, accessible to every builder. EOF providers (orange),
including MEV searchers and valuable order flow bots, monitor user
transactions and bundle them with their own transactions or directly submit
individual transactions to builders. Builders (purple) submit blocks with bids
to the relays (yellow), which make them available to the proposer (green)
through the mev-boost middleware.

##  3 Methodology

This section outlines the methodology for identifying transaction labels,
collecting empirical data, and calculating MEV-Boost block metrics.

###  3.1 Transaction Labels Taxonomy

We classify Ethereum transactions to understand the competitive edge different
types provide to block builders based on the payments they offer. To this end,
we determine a transparency and an order flow label for every transaction,
following the taxonomy presented in Figure 3.

####  3.1.1 Transparency Labels

Ethereum transactions submitted to public RPC endpoints propagate through a
peer-to-peer network and enter nodes’ public mempool. These transactions are
available to every builder running a node in the Ethereum network. However,
some transactions are submitted exclusively to a builder’s private RPC
endpoint, bypassing the public mempool. Additionally, certain transactions
submitted to private endpoints are revealed to a selected group of entities,
as occurs in OFAs. As part of our methodology, we apply the following
conditions to determine the transparency label of a transaction:

  * •

Public Signal: Recorded in the mempool of at least one monitored node.

  * •

Exclusive Signal: Not recorded in the mempool of any monitored nodes,
indicating exclusive submission to the block builder.

  * •

OFA Bundle: Part of an OFA bundle, either as the original user transaction or
the searcher backrun. The heuristics for identifying OFA bundles are detailed
in Section A.1.

Figure 3: Taxonomy of transaction transparency and order flow labels. Every
transaction has a transparency label (orange) based on its visibility on the
network level and an order flow label (purple) determined by its objective.
The gray labels stemming from the order flow labels represent the detailed
categories we consider or popular providers of such order flow.

####  3.1.2 Order Flow Labels

Ethereum transactions have various objectives, ranging from simple ETH
transfers to complex MEV strategies. Consequently, they have different
valuations for their originators, reflected through the payments offered to
block builders. To understand the impact of builders’ access to order flow on
their success in the MEV-Boost auction, it is critical to measure the value of
different order flow types. Therefore, we assign an order flow label for every
transaction included in our examined MEV-Boost blocks. While we consider
detailed categories, the taxonomy is not exhaustive and omits certain known
MEV strategies, such as Just-In-Time (JIT) liquidity [57] and cross-chain
arbitrages [72, 53], and misses unknown long-tail strategies employed by the
searchers.

We first determine if the transaction can be identified as a known MEV type,
such as an atomic DEX-DEX or a non-atomic CEX-DEX arbitrage, a sandwich
frontrun or backrun,444Sandwiched user transactions are labeled according to
their original objective. or a liquidation. If no MEV labels are matched, we
check if the transaction was submitted by a Telegram bot such as Banana Gun
[40] or Maestro [27]. These bots create wallets, store private keys for users,
and execute highly time-sensitive strategies on their behalf, such as token
mint sniping or long-tail token trading, in exchange for fees. Next, we
consider solver model transactions submitted by solvers, fillers, and
resolvers of protocols such as Cowswap[10], UniswapX[70], and 1inch Fusion
[1], fulfilling user limit orders. Additionally, as blockchain users require
CEXes like Binance [3] or Coinbase [8] to deposit and withdraw
cryptocurrencies, we also detect and label such transactions individually.
Further, if a transaction includes an ERC-20 token transfer or a swap but does
not belong to prior categories, we label it as retail swap or bot swap
depending on its initially interacted smart contract. If this contract is a
known, non-MEV contract such as the Uniswap Universal Router,555Uniswap
Universal Router contract address: 0x3fc91a3afd70395cd496c647d5a6cc9d4b2b7fad
we label the transaction as retail swap, likely originated through the
frontend of the respective protocol. Otherwise, we consider the transaction a
bot swap, interacting with an unlabeled contract, potentially executing long-
tail MEV strategies or known MEV strategies undetected by our datasets and
heuristics. We treat OFA bundle backrun as a distinct category, although user
transactions within OFA bundles are not labeled individually. Finally, any
remaining transaction is labeled as other public flow or other exclusive flow
depending on its transparency type. The former category includes transactions
like simple ETH transfers or batch submissions by rollup sequencers, while the
latter covers transactions such as MEV bot contract deployments by searchers.
The detailed identification methodology for each label is presented in Section
A.1.

###  3.2 Data Collection

We curate an empirical dataset covering a six-month period of MEV-Boost blocks
produced between October 1, 2023, and March 31, 2024, totaling
$1,190,617\text{\,}$ blocks. We primarily develop our data collection methods
using external platforms such as Dune Analytics [12] and open source them for
reproduceability by the community. We first build a compound query on Dune
[77], utilizing various datasets available on the platform [66, 68, 69, 67,
85, 63, 78]. Through this query, we identify transaction properties beyond the
standard payload data. These properties include transactions’ direct payments
to builders’ coinbase address, ERC-20 transfers, certain MEV activities, trade
volumes and fees in USD, MEV searcher and solver labels, Telegram bot labels,
router contract labels, and mempool visibility. We export the resulting
dataset, involving $174,240,225\text{\,}$ labeled transactions. Additionally,
we identify builder-controlled public keys using the extra data field of the
Ethereum blocks [76]. Finally, we obtain the remaining necessary data for our
methodology, such as all MEV-Boost payloads, bids on the UltraSound relay
[41],666UltraSound relay was one of the most dominant relays during the course
of this study [84]. further builder public keys and searcher addresses, and
other smart contract and transaction labels from external resources summarized
in Table 3 in Section A.2.

###  3.3 MEV-Boost Block Metrics

The value of an MEV-Boost block is derived from the transactions in it. Each
transaction offers a payment to the block builder, depending on its valuation
for the originator. There are two ways a transaction can make an on-chain
payment: through transaction fees and direct value transfers to the builder.
Based on the total value builders receive from these transaction payments and
their private valuation for the block, they offer a bid to the validator and
make a payment if they win the auction. In this section, we present the
methodology for calculating the true value, validator payment, and builder
profit of MEV-Boost blocks.

####  3.3.1 True Block Value

We define the set of MEV-Boost blocks we analyze in our study as $B$. For each
transaction $t\in T_{b}$, where $b\in B$ and $T_{b}$ represents all
transactions included in $b$, we denote its gas priority fee (i.e., tip) and
direct transfer to builder’s coinbase address as $t_{tip}$ and $t_{coinbase}$,
respectively. We refer to the refund amount of builder transactions in OFA
bundles as $t_{refund}$. For failed transactions included in $b$, we set their
coinbase payment to 0 and only consider their tip payment to the builder. We
define the true value ($TV$) of a block as:

$b_{TV}=\sum_{t\in
T_{b}}(t_{\text{tip}}+t_{\text{coinbase}}-t_{\text{refund}}).$

We note that $TV$ is only a best-effort estimate based on available on-chain
data. For a more robust measure, $TV$ calculation must account for private
valuations of the searchers and builders and off-chain payment deals.

####  3.3.2 Validator Payment

For a given MEV-Boost block $b$, we denote the validator payment ($VP$) as
$b_{VP}$, referring to the amount tipped to the designated validator’s
proposer fee recipient address by $b$. Although most MEV-Boost blocks involve
a builder transaction at the block’s last index to make this payment, there
are edge cases where the payment is made by an address related to the builder,
or there is no payment from the builder, and the validator’s proposer address
is set as the block’s fee recipient [4] . We assume the first case makes no
difference when calculating $b_{VP}$, but we omit the blocks from our analysis
where the proposer is set as the fee recipient. While builders can still
profits from such blocks if they have own searcher transactions or through
off-chain deals, since there is no on-chain value transfer to the builder, we
ignore them. This strategy might be used when the builder aims to gain market
share while avoiding the basefee for the validator payment transaction,
especially when the expected profit from the block is low. In Table 7 in
Section B.6, we summarize builders’ excluded blocks.

In this paper, we calculate $b_{VP}$ by identifying the validator payment
transaction. We avoid using the payload value reported by relays as $b_{VP}$
since this value can be manipulated if the relay calculates a builder’s bid
value by the balance difference of the proposer [5], leading to a
miscalculation of validator earnings. One reason for such discrepancies is
stake withdrawals [38]. When a builder includes a withdrawal transaction to
the validator of the block, such relays over-report the bid by considering the
withdrawal amount as part of the validator payment done by the builder,
potentially causing profit loss for the validator [11]. We share empirical
results of builders’ validator payment patterns in Table 7 in Section B.6.

####  3.3.3 Builder Profit

We denote the builder profit ($BP$) of an MEV-Boost block $b$ as $b_{BP}$.
When calculating $b_{BP}$, we handle the following edge cases:

  * •

Besides the validator payment and OFA refund transactions, we do not deduct
other builder value transfers from $b_{TV}$ when calculating $b_{BP}$. Since
such transfers can be issued to builder-controlled Externally Owned Accounts
(EOAs) or smart contracts, deducting their value or using builder coinbase
address balance change may underestimate $b_{BP}$ [4],

  * •

When the builder does not issue a validator payment transaction, we check if
the last transaction of the block still pays the validator. If that is the
case and the validator’s proposer address is not the fee recipient of the
block, we assume this payment is made on behalf of the builder, either by an
address associated with the builder or one controlled by the UltraSound relay.
The latter occurs when the builder opts to use UltraSound’s recently deployed
bid-adjustment feature [56], which alters the builder’s winning bid to be
$1\text{\,}\mathrm{w}\mathrm{e}\mathrm{i}$ above the second-best bid available
on any relay and refunds a proportion of the bid surplus. Before March 5,
2024, the entire difference was refunded, but since then, UltraSound has been
taking half of it, which is eventually transferred by the builder. We refer to
this relay payment ($RP$) value of block $b$ as $b_{RP}$. In Table 7 in
Section B.6, we present the total amount paid by each builder to UltraSound.

In this paper, we define the on-chain builder profits as
$b_{BP}=b_{TV}-b_{VP}-b_{RP}$, and calculate the profit margin ($PM$) of a
builder from $b$, referring to the share of true block value kept by the
builder, with $b_{PM}=\frac{b_{BP}}{b_{TV}}$.

###  3.4 Limitations

Our methodology has the following limitations:

  1. 1.

Transparency Labels: Accuracy is limited by the mempool dataset’s coverage
across node providers [63]. Determining transaction exclusivity across
builders requires access to losing MEV-Boost bids’ execution payload data,
which the relays do not publicly disclose.

  2. 2.

Order Flow Labels: Potentially includes false labels due to our strict
heuristics (see Section A.1) and use of external data (see Table 3 in Section
A.2).

  3. 3.

Builder Profits:

     * •

Overestimated if the builder has off-chain deals with providers such as MEV
searchers or Telegram bots, and pays them for accessing their order flow.

     * •

Underestimated if the builder is vertically integrated with any MEV searcher,
as we only consider on-chain profits made through priority fees and coinbase
transfers.

  4. 4.

MEV Searcher Labels: Not exhaustive as we cannot detect all the bots one
searcher operates, obscuring the significance of a single searcher across
multiple addresses.

  5. 5.

Bidding Data: Can be biased as we only consider bids on the UltraSound relay.

##  4 MEV-Boost Decomposition

We present our measurements, decomposing the MEV-Boost auction to identify
potential features driving builder success. First, we examine the builder
market to observe the dominant players in market share and profits. Next, we
analyze the order flow in MEV-Boost blocks to determine the most valuable
flows and which builders receive them. Finally, we explore various strategies
builders adopt to gain a competitive advantage in the auction.

###  4.1 Builder Market Structure

Between October 2023 and March 2024, $39\text{\,}$ different block builder
entities won the MEV-Boost auction, producing $1,190,617\text{\,}$ blocks.
beaverbuild, rysnc, and Titan (BRT) contributed the most blocks, accounting
for $34.86\text{\,}\%$, $22.98\text{\,}\%$, $22.74\text{\,}\%$ of the total,
respectively. In approximately $8\text{\,}\%$ of MEV-Boost blocks, the builder
set the fee recipient address as the proposer, with Titan responsible for
$92.86\text{\,}\%$ of these cases (see Table 7 in Section B.6). We suspect
Titan adopts this strategy when the block’s profits are insufficient to cover
the basefee of the validator payment transaction. In the following analyses,
we exclude these blocks for reasons discussed in Section 3.3.2.

In Figure 4, we show the market share (Figure 4(a)), cumulative profit (Figure
4(b)), and daily profit margin (Figure 4(c)) of BRT over time. On average,
these three builders construct $80\text{\,}\%$ of all blocks. We observe a
surge in Titan’s market share and profits since February 2024, surpassing
rsync in cumulative profits, approaching beaverbuild. Interestingly, when
measured in USD, Titan has the highest total profit, reaching roughly
$19.7\text{\,}\mathrm{M}$ USD, despite building fewer blocks than beaverbuild
and rsync, who earned $19.4\text{\,}\mathrm{M}$ USD and
$4.27\text{\,}\mathrm{M}$ USD, respectively. Although the profits we calculate
gives an insight about builders’ earnings, the exact values can be different
since we only consider the value provided through transaction priority fees
and coinbase payments. Currently, we miss the upstream value builders make
through their integrated searchers [64, 62]. Furthermore, we cannot track
profits accurately if builders have any off-chain settlement with order flow
providers.

Examining the builders besides BRT, we discover that only seven others have a
market share nearly $1\text{\,}\%$ or more (see Table 1). Together, these top
ten builders produced $97.67\text{\,}\%$ of the blocks but only earned
$83.85\text{\,}\%$ of the $52\text{\,}\mathrm{M}$ USD total builder profit.
This discrepancy highlights the diverse builder profiles, with different
specializations in gaining market share and profits.

(a)

(b)

(c)

Figure 4: Trends in the market share, profits, and profit margin of the top
three builders with highest market share, BRT, over time. Figure 4(a) is an
area plot highlighting the changes in market share owned by BRT and the
aggregated, remaining builders, denoted as “Others” in the legend. Figure 4(b)
is a line plot showing the cumulative ETH profits of the same entities. Figure
4(c) displays the daily profit margin changes of BRT. The area below 0 on the
y-axis is filled with red to indicate days when the builder was, on average,
unprofitable.

Table 1 summarizes the measurements for the top ten builders with the largest
market share.777We only consider the MEV-Boost blocks where the builder is the
fee recipient address. The various profiles of the builders are reflected in
their profitability metrics. flashbots and builder0x69 behave neutrally, not
winning blocks by paying more than they earn from the included transactions.
In contrast, jetbldr, penguin, and tbuilder heavily subsidize and maintain a
negative profit margin on average. However, except for tbuilder, remaining
builders are overall profiting.888This can be due that subsidizing builders
seldom earn significant profits, keeping them profitable. beaverbuild has the
highest profit margin at $5.4\text{\,}\%$ within the top ten, whereas across
all builders, I can haz block? and Ty For The Block have approximately
$40\text{\,}\%$ profit margins (see Table 5 in Section B.2).

We note that Titan has a lower profit margin than rsync, despite earning
significantly higher profits. While our profit calculation may not reflect
precise values due to discussed issues, the discrepancy between profits and
profit margin could be because Titan has more days with a negative profit
margin compared to the other two top builders, who maintain a more consistent
profit margin over time (see Figure 4(c)). As beaverbuild and rsync run their
own searchers [62, 64], they receive a more consistent order flow stream.
Conversely, Titan relies on external order flow providers who may not be as
consistent, resulting in some blocks with significant profits and others that
are entirely unprofitable. This pattern also supports our observation about
the high percentage of Titan blocks where the proposer is set as the fee
recipient (see Table 7 in Section B.6).

| Total | Market | Total | Total | Total | Profit
---|---|---|---|---|---|---
Builder | Blocks | Share | Validator Payment | Subsidy | Profit | Margin
| [#] | [%] | [ETH] | [ETH] | [ETH] | [%]
beaverbuild | $413,868\text{\,}$ | $37.91\text{\,}$ | $49,871.82\text{\,}$ | $-70.46\text{\,}$ | $7,341.62\text{\,}$ | $5.4\text{\,}$
rsync | $273,126\text{\,}$ | $25.02\text{\,}$ | $33,691.74\text{\,}$ | $-80.71\text{\,}$ | $1,679.73\text{\,}$ | $3.25\text{\,}$
Titan | $177,915\text{\,}$ | $16.3\text{\,}$ | $22,025.19\text{\,}$ | $-61.49\text{\,}$ | $6,083.95\text{\,}$ | $1.02\text{\,}$
flashbots | $74,636\text{\,}$ | $6.84\text{\,}$ | $6,918.79\text{\,}$ | $0.0\text{\,}$ | $48.22\text{\,}$ | $1.38\text{\,}$
builder0x69 | $35,083\text{\,}$ | $3.21\text{\,}$ | $3,878.92\text{\,}$ | $0.0\text{\,}$ | $434.64\text{\,}$ | $2.3\text{\,}$
jetbldr | $32,670\text{\,}$ | $2.99\text{\,}$ | $1,192.15\text{\,}$ | $-73.21\text{\,}$ | $11.41\text{\,}$ | $-12.45\text{\,}$
f1b | $16,716\text{\,}$ | $1.53\text{\,}$ | $1,251.63\text{\,}$ | $-12.39\text{\,}$ | $53.59\text{\,}$ | $-1.94\text{\,}$
Gambit Labs | $15,281\text{\,}$ | $1.4\text{\,}$ | $889.45\text{\,}$ | $-19.75\text{\,}$ | $78.42\text{\,}$ | $-4.03\text{\,}$
penguin | $14,622\text{\,}$ | $1.34\text{\,}$ | $1,028.28\text{\,}$ | $-41.77\text{\,}$ | $17.7\text{\,}$ | $-9.73\text{\,}$
tbuilder | $10,584\text{\,}$ | $0.97\text{\,}$ | $338.38\text{\,}$ | $-79.1\text{\,}$ | $-77.01\text{\,}$ | $-41.23\text{\,}$
Table 1: Market Share and Profitability Metrics of Top Ten Builders

###  4.2 Order Flow Breakdown

In this section, we analyze the order flow in the MEV-Boost blocks, focusing
on their transparency and significance. We use the labels defined in Section
3.1.

####  4.2.1 Transparency

We first examine the transparency of the Ethereum order flow. Recent work [88]
showed an increasing share of value coming from EOF. We confirm their findings
and examine the transparency of individual order flow labels and builders’
blocks.

In Figure 5(a), we show the share of true block value of each transparency
label over time. Exclusive transactions and bundles, referred to as exclusive
signal, provide $66.69\text{\,}\%$ of all value while consuming only
$19.6\text{\,}\%$ of blockspace in terms of gas (see Figure 5(b)). Similar to
the results in [88], we find that this flow constitutes $71\text{\,}\%$ of all
block value in more than $50\text{\,}\%$ of the blocks, with nearly five times
more value per unit of gas consumed than public signal. While almost all
blocks have at least one exclusive and one public transaction, OFA bundles
occur in only $4\text{\,}\%$ of them, highlighting the scarce adoption of such
protocols.999MEVBlocker and MEV-Share (through Flashbots Protect [51]) have a
larger volume if we consider the exclusive user transactions submitted to them
which were not part of an OFA bundle. We summarize our measurements of
transparency labels in Section B.6 in Section B.1.

Next, we investigate the transparency of individual order flow labels,
expecting certain types to avoid the public mempool to protect their valuable
strategies. As shown in Figure 5(c), every order flow label has a dominant way
its involved in Ethereum blocks, corresponding to more than half of its total
volume. Telegram bot flow and MEV strategies, including atomic and non-atomic
arbitrages, sandwiches,101010Sandwiches are mostly exclusive as we do not
account the sandwiched user transactions in this label. Such transactions are
labeled according to their original category, such as retail swap. and
liquidations, mostly bypass the public mempool. On average, $99\text{\,}\%$ of
all MEV order flow is exclusively submitted to the builders. Conversely,
retail and bot swap flows are primarily submitted to the public mempool,
exceeding $80\text{\,}\%$ of their total volume. Interestingly, a relatively
significant share of solver model flow is involved in OFA bundles
($1.28\text{\,}\%$), receiving refunds while fulfilling user trade orders.
Notably, Cowswap solver model is known to be forwarding its flow to the
MEVBlocker OFA protocol.

Finally, we assess the transparency of builders’ blocks. In Figure 5(d), we
present the share of total value the top ten builders with the largest market
share receive from public and exclusive signal and OFA bundles. BRT, with the
largest market share and most profits, receive the highest relative value from
EOF, exceeding $65\text{\,}\%$ of their total. The builders with the lowest
profit margins among the top ten, jetbldr and tbuilder, receive the least
value from EOF, with shares below $40\text{\,}\%$. Among builders outside the
top ten who have greater than $0.01\text{\,}\%$ market share, more extreme
concentrations are observed, with exclusive value shares ranging between
$1\text{\,}\%$ and $91\text{\,}\%$ (see Figure 11 in Section B.3).

(a)

(b)

(c)

(d)

Figure 5: Figure 5(a) and Figure 5(b) are area plots highlighting the share of
value provided and blockspace consumed (in gas) by each transparency label
over time. Figure 5(c) is a horizontal bar plot showing the transparency of
each order flow label, measured in total transaction volume. Figure 5(d) is a
horizontal bar plot indicating the share of value that the top ten builders
with the highest market share receive from each transparency label. Builders
on the y-axis are ordered in ascending order based on their market share, with
the builder with the highest share listed at the bottom. The legend in Figure
5(a) applies to all figures.

####  4.2.2 Significance

The order flow included in a block is a good estimator of its true value. To
understand valuable flows, we analyze MEV-Boost blocks for the significance of
the order flow labels. We find that Telegram bot and MEV order flows (see
Section 3.1.2) cumulatively contribute around $51\text{\,}\%$ of all block
value while consuming merely $10\text{\,}\%$ of all gas spent in MEV-Boost
blocks (see Figure 6(a)). These flows provide around $53\text{\,}\%$ of all
block value in more than half of the blocks. Notably, they are primarily
exclusively submitted to block builders, as shown in Figure 5(c). In contrast,
order flow labels such as retail swap and other public flow, most frequently
observed in the public mempool, cumulatively provide a little over a quarter
of the total block value while consuming more than $67\text{\,}\%$ of the
total blockspace. These measurements of order flow labels, also summarized in
Section B.6 in Section B.1, indicate that valuable order flow is predominantly
exclusively submitted, and blocks are mostly filled with less valuable, public
transactions.

One of the drivers of competition in the MEV-Boost auction is the order flow
builders receive [87]. As order flow labels have varying levels of public and
exclusive volume (see Figure 5(c)) and value (see Section B.6 in Section B.1),
we must analyze builders’ order flow compositions concerning these labels to
understand who possesses the valuable flow.

In Figure 6(b), we show the order flow composition of the top ten builders
with the highest market shares. Builders have varying compositions, with
certain builders receiving a more significant share from specific order flows
than others. Some of the most valuable flows, such as Telegram bot flow and
non-atomic arbitrages, are more significant in the compositions of the top
three builders, BRT, while almost all builders receive a considerable share of
sandwich flow, which is a common strategy among MEV searchers. Furthermore, we
examine the order flow composition of builders outside the top ten and
discover more remarkable concentrations, with a single order flow providing
more than $80\text{\,}\%$ of the total value a builder receives, such as the
sandwich flow of s0e2t, as shown in Figure 12 in Section B.3.

(a)

(b)

Figure 6: Figure 6(a) shows the significance of order flow labels over time.
The left and right panels depict the share of total block value provided and
blockspace consumed (in gas) by each order flow label. Figure 6(b) displays
horizontal bars representing the share of value the top ten builders with
highest market share receive from each order flow label. Builders on the
y-axis are ordered in ascending order based on their market share, with the
builder with the highest share listed at the bottom. Order flow labels in
Figure 6(b) use the same coloring as indicated in the legend in Figure 6(a).

###  4.3 Builder Strategies

MEV-Boost block builders adopt various strategies to gain a competitive edge.
While order flow makes up their value, bidding and latency strategies also
play an important role during the auction process [87]. In this section, we
measure the significance of four builder strategies.

####  4.3.1 Block Packing

Authors in [62] discuss the importance of accessing value from top block
positions to win the block auction. They show through a theoretical model that
builders who earn more from Top-of-Block (ToB) are likely to dominate the PBS
auction. We analyze the block packing strategies of builders to support this
outcome with empirical data. To this extent, we measure the share of the value
builders earn from ToB, Body-of-Block (BoB), and End-of-Block (EoB) positions.
We define ToB as the first $10\text{\,}\%$ of transactions based on their
normalized index in the block, following [54]. Similarly, EoB, denotes the
bottom $10\text{\,}\%$. Lastly, BoB represents the middle $80\text{\,}\%$ of
the block. Builder transactions are excluded to prevent skewing the data.

In Figure 7(a), we show the share of value the top ten builders by market
share earn from transactions in each position group. ToB contributes the most
significant value to all top builders except penguin, and BRT receive more
than $74\text{\,}\%$ of their block value from order flow in ToB. The
significance of ToB can be attributed to the fact that more than half of the
total EOF volume resides in this position, providing, on average,
$88.5\text{\,}\%$ of the total EOF value. Conversely, BoB and EoB only
contribute approximately $10.5\text{\,}\%$ and $1\text{\,}\%$ of the total EOF
value. Interestingly, Titan, Gambit Labs, and penguin receive a relatively
considerable value from EoB. These builders could be allowing MEV searching at
the end of their blocks, on the state transitioned to by the included
transactions, and receiving significant payment from the granted searchers.
The valuable block positions of the remaining builders are summarized in Table
5 in Section B.2.

####  4.3.2 Subsidization

Builders who have just entered the market, not receiving significant volumes
of valuable order flow, are expected to subsidize their blocks unless they run
their own MEV searchers [6]. Since we previously found that certain builders
have negative profits margins (see Table 1), we are interested in how
significantly they subsidize to the win the auction. Figure 7(b) shows the
shares of blocks the top ten builders with highest market shares profited,
subsidized, or were neutral, making dust amount or zero profit.111111We set
$0.001\text{\,}\mathrm{E}\mathrm{T}\mathrm{H}$ as the dust amount threshold.
Notably, these measurements are solely based on on-chain profits and may not
reflect the complete picture, as builders can profit from their integrated
searchers or return a percentage of the value to order flow providers.

The top three builders in market share, BRT, also have the highest shares of
profitable blocks, with beaverbuild exceeding $40\text{\,}\%$. While Titan is
neutral in approximately $50\text{\,}\%$ of their blocks, this share goes up
to $68\text{\,}\%$ when considering the blocks where they set the proposer as
the fee recipient as zero profit as well (see Table 7 in Section B.6).121212We
assume zero on-chain builder profit from such blocks although the builder can
still earn profits from their integrated searchers or off-chain deals, as
discussed in Section 3.3.2. flashbots and builder0x69 predominantly break
even, supporting the measurements summarized in Table 1. Conversely, jetbldr,
penguin, and tbuilder win more than $75\text{\,}\%$ of their blocks by
subsidizing, paying extra value on top of the on-chain value they receive from
their order flow. Among builders outside the top ten, some adopt a profit-only
strategy. Examples include Anon:0x83bee, Anon:0xb3a6d, I can haz block?, and
Ty For The Block, who were also labeled as profitable, high-profit margin
builders in Figure 1. The subsidization and profitability metrics of the rest
of the builders are available in Table 5 in Section B.2.

####  4.3.3 Exclusive Order Flow Access

EOF contributes the majority of value to MEV-Boost blocks, as shown by our
study (see Section 4.2.1) and previous works [14, 88]. We also discovered that
builders have varying level of EOF in their blocks (see Figure 5(d)),
indicating a non-uniform access. Extending studies on integrated builders and
prominent order flow providers [6, 62, 86, 64, 88], we examine the
significance of EOF providers for each builder. We consider providers
including, public entities such as Flashbots Protect131313Flashbots Protect is
considered as the provider of the flow received by Flashbots’s private RPC
endpoints, including MEV-Share OFA bundles. and MEVBlocker, MEV searchers, and
solvers.141414Solvers refer to the liquidity routing entity in the solver
model introduced in section 3.1.

Figure 7(c) presents the shares of EOF value that the top ten builders with
the highest market share receive from the seven most significant providers
based on total value. These providers contribute roughly $70\text{\,}\%$ of
all EOF value in more than half of the MEV-Boost blocks, and supply over
$48\text{\,}\%$ of EOF value to each builder in the top ten, except jetbldr,
who primarly sources EOF from other providers. We find that Flashbots Protect
and MEVBlocker appear consistently, likely due to their public EOF access
requirements, without needing private deals [88]. Maestro Telegram bot
provides considerable flow to each top builder, unlike Banana Gun, which sends
almost no flow to jetbldr, penguin, and tbuilder but provides significant
value to Titan, especially starting from February 2024 (see Figure 13(b) in
Section B.4). Additionally, jetbldr and tbuilder receive negligible EOF from
the well-known sandwich searcher bot, jaredfromsubway.eth, while penguin gets
more than $50\text{\,}\%$ of its EOF value from this provider, potentially
explaining the prominence of sandwich flow in their order flow composition
(see fig. 6(b)). Finally, SCP and Wintermute are highly significant only for
beaverbuild and rsync, respectively, as these providers are operated by them
[62, 64].151515PLM and Rizzolver solvers, identified to be belonging to
beaverbuild and rsync [78], are aggregated with SCP and Wintermute providers,
respectively. Further integrations and private deals could exist among the
remaining builders and EOF providers, as shown in Figure 14 in Section B.4.

####  4.3.4 Latency and Bidding

MEV-Boost block builders compete in latency when placing bids on the relays.
Although the proposer is expected to release the block at slot start [48], the
exact time is unknown. Due to the stochastic nature of this process, low
latency is beneficial for builders to update bids [14], reflecting changing
valuations for the block over time and reacting to other bids.

(a)

(b)

(c)

Figure 7: Figure 7(a) is a horizontal bar plot showing the share of value the
top ten builders by market share earn from ToB, BoB, and EoB. Figure 7(b) is a
horizontal bar plot presenting the share of blocks the top ten builders
profited, subsidized, or made dust amount or zero profit. Figure 7(c) is a
horizontal bar plot displaying the share of EOF value the top ten builders
receive from the seven most significant EOF providers based on total value. In
the plot legend, “jaredsubway” and “FB Protect” stand for
“jaredfromsubway.eth” and “Flashbots Protect” providers, respectively. The
total EOF value of the remaining providers is aggregated and denoted as
“Others”. In all figures, builders on the y-axis are ordered from top to
bottom in ascending order of market share.

Using data from the UltraSound relay, we examine MEV-Boost builders’ latency
and bidding behavior. We measure their bidding frequency by the average number
of bids they place in each slot. Furthermore, we calculate the lag between
their bid updates to understand how quickly they can reflect their new
valuation and react to other bids. Lastly, we identify cases where builders
strategically lowered their bid values through cancellations [45], a strategy
discussed to be especially useful for builders running CEX-DEX arbitrage bots
[14].

In Table 2, we summarize the bidding behavior of the top ten builders in
market share for the blocks they won on UltraSound. We observe that the market
share gap between rsync and Titan became more significant compared to their
market shares when considering blocks from all relays (see Table 1), with a
jump from approximately $8.7\text{\,}\%$ to $12.2\text{\,}\%$. This could be
because the UltraSound relay allows optimistic submissions [33], potentially
favoring integrated builders such as beaverbuild and rysnc [62, 64], as they
can more frequently update their bids based on the value they derive from
their searchers.

We measure that the top ten builders have diverse bidding strategies, with the
average number of placed bids ranging from $6.1\text{\,}\mathrm{b}$y tbuilder
to $49.64\text{\,}\mathrm{b}$y penguin, who also has the lowest average update
lag between all of their bids in a slot (see Table 2). Builders can update
bids quickly and frequently by having low latency relative to the relay’s
geographical position or by submitting new bids simultaneously from multiple
public keys they control.

BRT, who won the most auctions on the UltraSound relay, issue the highest
number of cancellations, with, on average, more than one cancellation per
block.161616The average number of cancellations BRT issue per block increases
from $1.85\text{\,}$ to $2.09\text{\,}$ after the introduction of UltraSound’s
bid adjustment feature [56]. We note that, two of these builders, beaverbuild
and rysnc, have relatively high non-atomic arbitrage shares (see Figure 6(b))
and were identified to be running their own CEX-DEX arbitrage searchers [62,
64]. Therefore, we confirm findings in [14] regarding the use of cancellations
by integrated builders. We also observe that some builders outside the top
ten, such as antbuilder, who also has a relatively large non-atomic arbitrage
flow (see Figure 12 in Section B.3), issued around ten cancellations per block
they built (see Table 6 in Section B.5).

We note the distribution of average winning times for builders, referring to
the average slot time a builder’s winning blocks were selected by the
proposer. While the winning time for each builder is beyond the slot start
(0ms), possibly due to timing games [74, 89], there is approximately a
$580\text{\,}\mathrm{m}\mathrm{s}$ difference between the earliest and the
latest winner times. This difference can be related to the slot times builders
start and stop bidding in the auction [14].

##  5 Results

In this section, we identify the features associated with gaining market share
and earning profits in the MEV-Boost auction. We apply a Spearman correlation
with a p-value set to $0.05\text{\,}$ to assess the strength and direction of
the associations based on rank orders. Spearman is used instead of Pearson to
reduce sensitivity to outliers, which could be an issue due to the diverse set
of block builders in our study. We exclude builders with less than
$0.01\text{\,}\%$ market share, focusing on the remaining $33\text{\,}$
builders (see Table 5 in Section B.2).

| Total | Avg. | Avg. | Avg. | Total | Avg.
---|---|---|---|---|---|---
Builder | Blocks | Bids | Update Lag | Winner Time | Cancels | Cancels
| [#] | [#] | [ms] | [ms] | [#] | [#]
beaverbuild | $137,721\text{\,}$ | $31.54\text{\,}$ | $130.41\text{\,}$ | $586.59\text{\,}$ | $248,195\text{\,}$ | $1.74\text{\,}$
rsync | $95,310\text{\,}$ | $25.27\text{\,}$ | $166.21\text{\,}$ | $531.38\text{\,}$ | $212,504\text{\,}$ | $2.29\text{\,}$
Titan | $47,539\text{\,}$ | $31.11\text{\,}$ | $186.25\text{\,}$ | $605.83\text{\,}$ | $91,337\text{\,}$ | $1.78\text{\,}$
flashbots | $32,612\text{\,}$ | $16.25\text{\,}$ | $411.36\text{\,}$ | $348.45\text{\,}$ | $3,014\text{\,}$ | $0.1\text{\,}$
builder0x69 | $23,294\text{\,}$ | $20.64\text{\,}$ | $183.08\text{\,}$ | $575.09\text{\,}$ | $17,445\text{\,}$ | $0.65\text{\,}$
jetbldr | $12,960\text{\,}$ | $35.2\text{\,}$ | $103.08\text{\,}$ | $605.75\text{\,}$ | $904\text{\,}$ | $0.09\text{\,}$
Gambit Labs | $9,530\text{\,}$ | $15.85\text{\,}$ | $349.05\text{\,}$ | $496.3\text{\,}$ | $492\text{\,}$ | $0.1\text{\,}$
f1b | $9,242\text{\,}$ | $25.42\text{\,}$ | $214.18\text{\,}$ | $680.45\text{\,}$ | $10,494\text{\,}$ | $0.98\text{\,}$
penguin | $7,783\text{\,}$ | $49.64\text{\,}$ | $69.92\text{\,}$ | $652.91\text{\,}$ | $966\text{\,}$ | $0.13\text{\,}$
tbuilder | $4,786\text{\,}$ | $6.1\text{\,}$ | $476.68\text{\,}$ | $104.71\text{\,}$ | $81\text{\,}$ | $0.01\text{\,}$
Table 2: Bidding and Latency Metrics of Top Ten Builders (UltraSound Relay)

###  5.1 Order Flow Diversity

The diversity of order flow a builder receives can indicate access to multiple
sources, making the builder more competitive in auctions compared to those who
depend on a specific order flow type, which may not always be available. To
capture this, we measure the Shannon entropy [71] of builders’ order flow.
With twelve unique order flow labels (see Section 3.1.2), the Shannon entropy
is defined as $H(X)=-\sum_{i=1}^{12}p_{i}\log_{2}(p_{i})$, where $p_{i}$
represents the value share of each label in a builder’s order flow
composition. Higher entropy values indicate a more diverse order flow, while
smaller values signify a concentrated composition.

In the left panel of Figure 8, we show the entropy value of each builder’s
order flow composition. The top ten builders with the most market share have
entropy values closer to the maximum ($H_{\text{max}}=\log_{2}(12)\approx
3.585$). However, among builders with smaller market shares, lower values are
observed, suggesting a concentration around a few order flow labels. To better
understand the order flow concentration, we measure builders’ highest value
share label, denoted as Most Significant Order Flow (MSOF). The outcome in the
right panel of Figure 8 shows that the top ten builders have various MSOFs
labels, although all have less than $32\text{\,}\%$ value share. In contrast,
across the remaining builders, MSOF value share can exceed $70\text{\,}\%$,
indicating a highly concentrated order flow composition.

To examine the link between builders’ success in winning the auction and the
diversity of their order flow, we measure the correlation between builders’
market share and order flow entropy. We find a significant positive
correlation, with a coefficient of $0.66\text{\,}$ and a p-value of
$2.22e-05$. This suggests that builders receiving different order flow types
have an advantage in the auction and can win more frequently, as they are not
dependent on a single type of flow. Conversely, builders with a concentrated
order flow composition, where MSOF is more prominent, can only be competitive
when that specific order flow type is available.

###  5.2 Exclusive Providers

MEV-Boost block builders receive EOF from various providers, as discussed in
Section 4.3.3. Builders with own providers, such as beaverbuild and rsync [62,
64], can produce profitable blocks as they access order flow not shared with
others. To identify such exclusive relationships, we employ Linear
Discriminant Analysis (LDA), classifying providers that can successfully
separate a builder’s blocks from others. We consider the model’s Decoding
Accuracy (DA) to be significant if it exceeds a threshold calculated using a
binomial cumulative distribution [58].

In Figure 9, we present a heatmap showing the DA of EOF providers for each
builder with at least one statistically significant provider. Unidentified
providers are enumerated according to the mapping in [79]. A high DA indicates
that the builder is distinguished by the significance of EOF they receive from
the provider. If an EOF provider is prominent for many builders, it can be
considered a neutral provider, accessible by all. Conversely, an EOF provider
will be significant for only a single builder if they are vertically
integrated or have an exclusivity deal. We define these providers as EPs,
identifiable by columns with a single colored cell in the heatmap.

Figure 8: The left panel is a horizontal bar plot presenting each builder’s
order flow diversity through a Shannon entropy value. Builders are ordered
from top to bottom in ascending order of market share. The right panel is a
horizontal bar plot depicting each builder’s MSOF, referring to their highest
value order flow label (in percentage). Bars are colored based on the order
flow label.

We find that approximately $55\text{\,}\%$ of the builders have at least one
EP. These builders have a higher rate of profitable blocks ($46\text{\,}\%$)
compared to those without any EP ($20\text{\,}\%$). This result is supported
by a Chi-square test on the number of profitable blocks built by the two sets
of builders (Chi-square = $33,077.29\text{\,}$, p $<$0.05\text{\,}$$).
Additionally, we find a positive correlation between the rate of profitable
blocks and whether builders have an EP, with a coefficient of $0.4\text{\,}$
and a p-value of $0.02\text{\,}$.

Our results suggests that to produce profitable blocks, builders need
exclusive relationships with providers who only supply significant EOF to
them. We note that the correlation we measured could have been stronger if EP
profits were accounted towards builders, as certain EPs, such as integrated
searchers, do not necessarily reflect all the value they extract in their
builder payments (see Section 3.4). Interestingly, around $46\text{\,}\%$ of
the builders with a negative profit margin (see Table 5 in Section B.2) have
an EP, indicating that the value they subsidize on-chain could already be
covered by the profits of their provider.

###  5.3 Key Features for Market Share and Profitability

The MEV-Boost decomposition revealed various features potentially associated
with builders’ success in winning blocks and earning profits (see Section 4).
We find that, for the top ten builders who produced the most blocks, there is
a significant positive correlation between their market share and profit
margin (coef = $0.87\text{\,}$, p $<$0.05\text{\,}$$). Additionally, we
identify overlapping features correlated with both metrics (see Figure 10),
suggesting that the skills needed to succeed in both areas of the auction are
similar.

Exclusive signal, non-atomic arbitrages, and Telegram bot flow strongly
positively correlate with both market share (see Figure 10(a)) and profit
margin (see Figure 10(b)), whereas public signal, including retail swaps,
negatively correlates with them. This suggests that high-market share builders
receive the more valuable exclusive flows, enabling them to keep significant
profits, while those with smaller shares must fill their blocks with less
valuable public transactions. For similar reasons, we observe a positive
correlation of top ten builders’ market share with their profitable block
rate,171717Correlation between profit margin and profitable block rate is
omitted as they are related by definition. and a negative correlation with
their subsidy rate. Thus, we encounter the “chicken-and-egg” problem described
in [6]: builders cannot profit from their blocks if they do not have order
flow differentiating them from others, and they do not receive such flow
unless they have a significant market share.

Furthermore, top ten builders’ success in gaining market share is strongly
positively correlated with the value they derive from order flow in ToB,
supporting the findings in [62] (see Figure 10(a)). Conversely, BoB has the
strongest negative correlation. Similar correlations are observed with
builders’ profit margin (see Figure 10(b)). We expect that valuable EOF
received by successful builders is prioritized for execution at ToB, allowing
them to operate on the latest transitioned state and avoid unexpected changes
caused by prior transactions.

Figure 9: Heatmap displaying the DA of EOF providers (x-axis) for each builder
(y-axis). Colored cells indicate a statistically significant DA, whereas gray
cells show negligible values. Columns with a single colored cell indicate EPs.

Finally, we find that builders’ market share and profit margin are positively
correlated with the number of bid cancellations they place per block they win
on the UltraSound relay, as shown in Figure 10. This highlights the importance
of such bidding strategies during the auction process, allowing builders to
lower their active bid, either to avoid making a loss due changing private
valuation for the block or to keep higher profits if there is a significant
gap with the second highest bid. This is also facilitated by the bid
adjustment feature of UltraSound [56]. Interestingly, we do not find a
significant correlation with bid update lag, suggesting that latency is not
necessarily linked with succeeding in the auction. However, this result may be
biased as our latency analysis only considers the blocks relayed through
UltraSound. For definitive results, bidding data on other relays must be
examined as well.

##  6 Discussion

The current PBS implementation, MEV-Boost, has successfully enabled uniform
access to MEV rewards for Ethereum validators, thereby avoiding centralization
of the consensus participants. However, the current design of the block
building auction promotes competition in EOF access and latency, raising the
barrier to entry for new builders and leading to a centralized market (see
Section 5). While this centralization is not as detrimental to the protocol’s
security as a centralized validator set, it still undermines Ethereum’s
censorship resistance [61, 81] and neutrality [42] properties.

MEV-Boost block builders are incentivized to access valuable order flow from
diverse sources and, notably, from distinguished EPs (see Section 5). The top
two builders with the highest market shares, beaverbuild and rsync, are
operated by HFT firms running integrated searchers specializing in non-atomic
arbitrages [62, 64]. The third best builder, Titan, appears to have an
exclusive deal with the Banana Gun Telegram bot starting from February 2024
(see Section 4.3.3). The current market dominance by three players, who build
approximately $80\text{\,}\%$ of MEV-Boost blocks (see Section 4.1), raises
the barrier of entry for builders, requiring them to secure order flow deals
and operate their own searchers to become competitive [6]. Builders unable to
do so are forced to adopt subsidy strategies, which are unsustainable in the
long run.

Furthermore, builders with a latency advantage due to advanced infrastructure,
such as HFT firms, can scale up by running multiple instances and adjusting
bid values until the last milliseconds of the block auction (see Section
4.3.4) . This gives them an edge in reacting to others’ bids and placing
cancellations, at the cost of further raising barriers to entry, misaligning
validators’ incentives, and increasing the auction’s gameability [45].

(a)

(b)

Figure 10: Spearman rank correlations of order flow and builder strategy
features for the top ten builders with the highest market share. Figure 10(a)
is a horizontal bar plot showing the significant correlations between features
and builders’ market share. Figure 10(b) is a horizontal bar plot presenting
the significant correlations between features and builders’ profit margin.

To uphold Ethereum’s censorship resistance and neutrality, it is essential to
foster competition and maintain a sufficiently decentralized builder market.
There are multiple solution directions for achieving this:

  * •

Changing Auction Format: To diminish the impact of latency and bidding
strategies, the block auction format can be changed to a sealed-bid auction,
eliminating adaptive bidding strategies [87]. However, such an opaque design
requires further consideration to reduce dependency on relay intermediaries
for not disclosing bid values while maintaining an efficient auction, secure
against collusion between the builders and the relays via side-channels.

  * •

Decentralized Builders: Solutions to decentralize the block builder role, such
as SUAVE [24],181818SUAVE is currently under development [22]. aim to remove
social trust in builder by running block building logic in privacy-preserving
execution environments like Trusted Execution Environments (TEEs). They can
contribute to a less monopolized builder market if they become competitive by
attracting a diverse set of order flow providers. Features like gas fee
refunds [25], making searchers pay the second-best price of the bundles
competing for access to the same state, can also help achieve this.

  * •

Redistributing and Reducing MEV: Capturing the MEV extracted by searchers and
redistributing it could decrease the value leaked to builders and, eventually,
to validators. Solutions for this include MEV-aware decentralized applications
(e.g., DEXes [1, 10, 37, 70]), intermediary protocols like OFAs [29, 52], and
further mechanisms such as MEV taxes [34]. Additionally, encrypted mempools
(e.g., Shutter Network [75], SUAVE [24]) where users send encrypted
transactions that are decyrpted before execution, can prevent censoring and
potentially reduce the MEV exposed.

  * •

In-Protocol Mechanisms: In-protocol mechanisms such as inclusion lists [32,
23] and concurrent proposers [61, 9] enforce the involvement of a set of
transactions/bundles in a produced block. This could strengthen Ethereum’s
censorship resistance properties by reducing the monopoly of a single builder
over the block payload, making block production a cooperative activity.
Moreover, further unbundling consensus from execution by clearly separating
block proposal and attesting duties, referred to as Attestor-Proposer
Separation (APS), would allow shielding attesters from centralizing forces.
Both execution tickets [18] and execution auctions [17] are proposals in that
direction, and are discussed along with inclusion lists to prevent timing
games [74, 89] without introducing new MEV vectors [31].

Overall, the discussed solutions propose various ways to address the
censorship threat posed by the currently centralized block builder market. We
hope our study provides valuable insights and considerations for designing
further iterations of such mechanisms and Ethereum block auctions, preserving
Ethereum’s censorship resistance properties.

##  7 Conclusion

In this paper, we examined the MEV-Boost auction to identify features
significant for winning blocks and earning profits. We found that builders’
order flow diversity and access to order flow by EPs are correlated with their
block market share and profitability, respectively. Additionally, we showed a
positive correlation between market share and profit margin among the top ten
builders, suggesting a “chicken-and-egg” problem where builders need order
flow distinguishing them from others to profit but only receive such flow if
they have a significant market share. Finally, we discussed how the key
features we identified for success in MEV-Boost raise the barrier of entry for
new builders, driving the builder market towards centralization, and explored
existing solutions for preserving Ethereum’s censorship resistance properties,
hoping the insights we provide help move the solution space forward.

## Acknowledgements

We thank The Latest in DeFi Research (TLDR) program, funded by the Uniswap
Foundation, for supporting this work. Special thanks to Flashbots and Eden for
generously providing data. We also express our gratitude for the valuable
reviews of Julian Ma, Xin Wan, Christof Ferreira Torres, Kevin Pang, Žan
Knafelc, and Tesa Ho.

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##  Appendix A Additional Methodology

###  A.1 Label Identification

####  A.1.1 OFA Bundles

We consider an OFA bundle structure of a user transaction $t^{i}$ at block
position index $i$, a backrun transaction $t^{i+1}$, and a builder refund
transaction $t^{i+2}$ which rebates a proportion of the backrun’s paid fee to
the user or the OFA, which then distributes it. We also identify cases where
an OFA bundle is backrunned by another OFA bundle structure, only involving a
backrun transaction and a refund, without a user transaction.191919Example of
a two-transaction OFA bundle:  • Backrun:
0x2a6b88d73d939310e59b569ef7acf0fe6ae9df97db5d1a2a8006218d1a713cd2 • Refund:
0x7e5b3622c83694aabbc298df1c524d1b02736a995dd25deb20353f652ed29683 Overall, we
identify three bundle structures, examining adjacent transactions by index,
with the following heuristics:

  * •

Cowswap-MEVBlocker Bundle

    1. 1.

$t$ is issued to the Cowswap settlement contract,202020Cowswap Protocol
Settlement address: 0x9008D19f58AAbD9eD0D60971565AA8510560ab41

    2. 2.

$t^{i+1}_{priorityfee}+t^{i+1}_{coinbase}\geq t^{i+2}_{value}$,212121This
condition is enforced to ensure that the builder’s refund transaction
transfers at most the complete fee payment it received from the backrun
transaction.

    3. 3.

$t^{i+2}$ transfers value to the MEVBlocker Gnosis Safe
address,222222MEVBlocker Gnosis Safe address:
0xce91228789b57deb45e66ca10ff648385fe7093b

    4. 4.

$t^{i+2}$ is issued by the builder of the block.

  * •

Matching Address Bundle

    1. 1.

$t$ involves an ERC-20 transfer or a swap,

    2. 2.

$t^{i+1}_{priorityfee}+t^{i+1}_{coinbase}\geq t^{i+2}_{value}$,

    3. 3.

$t^{i+2}$ transfers value to the sender of $t$,

    4. 4.

$t^{i+2}$ is issued by the builder of the block.

  * •

MEV-Share Bundle

    1. 1.

$t$ involves an ERC-20 transfer or a swap,

    2. 2.

$t^{i+1}_{priorityfee}+t^{i+1}_{coinbase}\geq t^{i+2}_{value}$,

    3. 3.

$t^{i+2}$ transfers value to a known MEV-Share refund address [20],

    4. 4.

$t^{i+2}$ is issued by the builder of the block.

####  A.1.2 MEV

We detect certain MEV strategies, such as atomic arbitrages, sandwiches, and
liquidations, using the labels provided by zeromev[44]. For arbitrages and
sandwiches, we combine zeromev data with labels available on Dune Analytics
collections [66, 68, 69]. We programmatically identify all victim transactions
in a sandwich bundle.

####  A.1.3 Non-Atomic Arbitrages

We detect non-atomic CEX-DEX arbitrages, introducing heuristics inspired from
[46, 86, 64]. We label a transaction $t^{i}$ at a normalized block position
$i$ as a non-atomic arbitrage if it fulfills all of the following heuristics:

  1. 1.

$t$ has a sufficient gas fee or does coinbase payment [64]:232323If $t^{i-1}$
or $t^{i+1}$ has the same sender as $t$ and make a coinbase transfer, we also
consider it as a payment for $t$ [46, 86] $t_{tip}\geq 1Gwei$ or
$t_{coinbase}>0$ ,

  2. 2.

$t$ is not seen in the public mempool,

  3. 3.

$t$ does not have an MEV label and is not part of an OFA bundle,

  4. 4.

$t$ makes strictly two ERC-20 token transfers (or one swap) and uses less than
$400,000\text{\,}$ gas [64],

  5. 5.

$t$ is the first swap in the pool considering trade direction (i.e., the first
sell and buy are both seen as the first swap) [64],

  6. 6.

$t$ is not submitted to a known router smart contract identified in [78].

####  A.1.4 Telegram Bot Flow

We use a dataset available on Dune Analytics [85] to identify the smart
contracts and trades of $21\text{\,}$ Telegram bots and one web trading
portal.

####  A.1.5 Solver Model Flow

In this work, we focus on Cowswap[10], UniswapX[70], and 1inch Fusion[1]
solver models. Since solvers and fillers operating on them submit their
solutions to the router contracts of these platforms, we detect solver model
flow by checking the destination address of the transactions. We identify such
router contracts using the Dune Analytics dataset by [78].

####  A.1.6 CEX

We detect CEX deposits utilizing a collection available on Dune Analytics
[67]. This dataset includes $1,922\text{\,}$ deposit wallet addresses of
$301\text{\,}$ CEXes.

####  A.1.7 Swap Flow

We identify transactions that involve an ERC-20 transfer (or a swap) and do
not belong to other order flow label categories as swap flow. We differentiate
between retail and bot swap by checking whether the transaction is directed to
a known, non-MEV smart contract, indicating a retail swap. For this, we use
the router addresses made available by [78] and labeled contracts dataset [36]
used in [86]. The retail swap category also involves the bundled user
transactions in OFAs and sandwiches. If the transaction does not initially
interact with a labeled contract, we categorize it as bot swap.

####  A.1.8 Others

We label the transactions that do not belong to any other order flow category
as other public or exclusive flow based on their visibility in the network,
using the mempool data by [63].

###  A.2 External Data

As part of our methodology, we used datasets from external resources,
summarized in Table 3.

##  Appendix B Further Measurements

###  B.1 Order Flow Overview

In Section B.6, we summarize our measurements for transparency and order flow
labels.

####  B.1.1 Occurance and Trends

We find that Telegram bot transactions appear more often in blocks
($0.89\text{\,}$ per block) than common MEV strategies such as sandwiches
($0.58\text{\,}$) and arbitrages (atomic: $0.16\text{\,}$, non-atomic:
$0.68\text{\,}$), as summarized in Section B.6. The frequency of occurrences
we calculate for MEV order flow types differs from [64], which covers MEV-
Boost blocks up to October 31, 2023. As we show in Figure 6(a), the
significance of order flow labels changes over time, with certain types
becoming more popular. For example, Telegram bot transactions consistently
provided the most value until the last week of 2023. Afterwards, we observe
oscillations, with sandwiches and non-atomic arbitrages gaining prominence.
These trends in the order flow landscape could explain the different
measurements compared to [64].

Interestingly, the gas consumed by other public flow decreases in March 2024
(see Figure 6(a)). As discussed in Section 3.1.2, this order flow includes
transactions such as batch submissions by rollup solutions, potentially
consuming high amounts of gas. Following the Dencun upgrade on March 13, 2024
[7], which introduced blob transactions to save gas costs for rollups, we
notice a drop in the daily average gas used by other public flow from
$35\text{\,}\%$ to $27.5\text{\,}\%$. This is another evidence of how the
order flow landscape can evolve over time.

###  B.2 All Builders Overview

In Table 5, we summarize all builders’ market share, profitability, and block
packing metrics.

###  B.3 Builder Order Flow

In Figure 11 and Figure 12, we show the order flow transparency and
composition of every builder, respectively.

###  B.4 Exclusive Order Flow Providers

In Figure 13(a), we show the trends in the significance of the seven EOF
providers who contributed the most value to MEV-Boost blocks. The emergence of
the Maestro Telegram bot coincides with a major decrease in the significance
of Flashbots Protect and MEVBlocker, supporting the findings in [88].
Additionally, Banana Gun Telegram bot gains a traction at the beginning of
February 2024, which we observe to be overlapping with the surge in Titan’s
market share (see Figure 4(a)) and profits (see Figure 13(b)), suggesting an
EOF deal.242424The spike in Figure 13(b), observed on January 19, 2024, is due
to a failing RPC endpoint of Titan [80]. Conversely, beaverbuild and rsync
consistently made profits over time, likely due to their integrated searchers
SCP and Wintermute [62, 64], respectively (see Figure 13(c), Figure 13(d)).

In Figure 14, we present the significance of EOF providers for MEV-Boost
builders with greater than $0.01\text{\,}\%$ market share. As we could not
match most of the providers with known entities, we enumerate them and share
this mapping in [79].

Data | Source
---|---
Certain MEV and swap transactions |  zeromev [44]
Non-MEV smart contract addresses |  searcherbuilder.pics [86]
Searcher addresses |  Etherscan [60], Arkham [2], libMEV [26]
Bids submitted to the UltraSound relay |  Eden Network [13]
Payloads of all MEV-Boost auctions |  relayscan.io [30]
Public keys controlled by the builders |  Builder Websites, Eden Network [13]
MEVBlocker transactions/bundles |  Dune Analytics [49]
Flashbots Protect and MEV-Share transactions/bundles |  Flashbots Data [20]
Table 3: External Data Sources

###  B.5 Latency and Bidding

In Table 6, we summarize the latency and bidding behavior of all builders for
the blocks they won on the UltraSound relay.

###  B.6 Validator Payment

In Table 7, we summarize builders’ validator payment patterns. Excluded blocks
correspond to MEV-Boost blocks where the builder sets the proposer as the fee
recipient. Other fee payer blocks are the ones where the fee recipient builder
address does not conduct the proposer payment, but a related address does it.
We include such blocks in our analysis as the builder is assumed to eventually
pay the original payer. Further, we measure the difference between the value
indicated in the blocks’ payload value obtained from MEV-Boost relays and the
actual value paid to the validator. Here, we calculate the over-promised value
(promised but not paid to the proposer) and the under-promised value (paid to
the proposer on top of the promised value). Finally, we calculate the relay
payment done by the builder, which occurs if the builder uses UltraSound’s bid
adjustment feature [56].

We observe that Titan produced many blocks which were excluded from our
analysis. While Titan did not receive on-chain value from these blocks, they
helped the builder to gain market share, as discussed in Section 3.3.2.
Moreover, flashbots and penguin have over-promised a considerable amount,
potentially by including withdrawal transactions in their blocks. Finally, we
detect that only BRT used the bid adjustment feature of the UltraSound relay,
as no other builders made a relay payment.

|  | Occurrence | Avg. | Avg. | Value | Avg.
---|---|---|---|---|---|---
Type | Label | Probability | Value | Share | per Gas | Gas
|  | $P$ | [ETH] | [%] | [ETH] | [%]
| Exclusive Signal | 0.99 | 0.12 | 66.69 | $7.5e-09$ | 19.6
Transparency | Public Signal | 1.0 | 0.02 | 33.0 | $1.3e-09$ | 80.26
| OFA Bundle | 0.04 | $<0.01$ | 0.31 | $1.8e-11$ | 0.14
1-7 | Telegram Bot Flow | 0.89 | 0.04 | 18.64 | $2.4e-09$ | 5.93
| Sandwich MEV | 0.58 | 0.03 | 17.49 | $1.8e-09$ | 1.7
| Bot Swap Flow | 1.0 | 0.02 | 10.09 | $1.2e-09$ | 12.69
| Non-Atomic Arbitrage MEV | 0.68 | 0.02 | 13.22 | $1.2e-09$ | 1.52
| Retail Swap Flow | 1.0 | 0.01 | 13.89 | $5.9e-10$ | 33.33
Order | Other Public Flow | 1.0 | 0.01 | 13.73 | $5.6e-10$ | 34.28
Flow | Atomic Arbitrage MEV | 0.16 | 0.01 | 1.49 | $3.4e-10$ | 0.41
| Other Exclusive Flow | 0.87 | 0.01 | 3.34 | $3.4e-10$ | 1.44
| CEX Deposits | 0.99 | $<0.01$ | 5.96 | $2e-10$ | 7.22
| Solver Model Flow | 0.52 | $<0.01$ | 1.9 | $1.1e-10$ | 1.42
| Liquidation MEV | $<0.01$ | $<0.01$ | 0.03 | $6.7e-11$ | 0.01
| OFA Backrun | 0.04 | $<0.01$ | 0.22 | $1.4e-11$ | 0.05

Table 4: Summary of Transparency and Order Flow Labels

| Total | Market | Total | Total | Total | Profit | Profitable | Dust/Zero Profit | Subsidized | ToB | BoB | EoB
---|---|---|---|---|---|---|---|---|---|---|---|---
Builder | Blocks | Share | Payment | Subsidy | Profit | Margin | Blocks | Blocks | Blocks | Value | Value | Value
| [#] | [%] | [ETH] | [ETH] | [ETH] | [%] | [%] | [%] | [%] | [%] | [%] | [%]
beaverbuild | $413,868\text{\,}$ | $37.91\text{\,}$ | $49,871.82\text{\,}$ | $-70.46\text{\,}$ | $7,341.62\text{\,}$ | $5.4\text{\,}$ | $45.11\text{\,}$ | $46.26\text{\,}$ | $8.63\text{\,}$ | $74.55\text{\,}$ | $25.17\text{\,}$ | $0.27\text{\,}$
rsync | $273,126\text{\,}$ | $25.02\text{\,}$ | $33,691.74\text{\,}$ | $-80.71\text{\,}$ | $1,679.73\text{\,}$ | $3.25\text{\,}$ | $39.05\text{\,}$ | $58.6\text{\,}$ | $2.35\text{\,}$ | $74.15\text{\,}$ | $25.18\text{\,}$ | $0.66\text{\,}$
Titan | $177,915\text{\,}$ | $16.3\text{\,}$ | $22,025.19\text{\,}$ | $-61.49\text{\,}$ | $6,083.95\text{\,}$ | $1.02\text{\,}$ | $27.42\text{\,}$ | $52.48\text{\,}$ | $20.1\text{\,}$ | $74.91\text{\,}$ | $20.5\text{\,}$ | $4.59\text{\,}$
flashbots | $74,636\text{\,}$ | $6.84\text{\,}$ | $6,918.79\text{\,}$ | $0.0\text{\,}$ | $48.22\text{\,}$ | $1.38\text{\,}$ | $15.66\text{\,}$ | $84.34\text{\,}$ | $0.0\text{\,}$ | $72.32\text{\,}$ | $27.31\text{\,}$ | $0.37\text{\,}$
builder0x69 | $35,083\text{\,}$ | $3.21\text{\,}$ | $3,878.92\text{\,}$ | $0.0\text{\,}$ | $434.64\text{\,}$ | $2.3\text{\,}$ | $23.75\text{\,}$ | $76.25\text{\,}$ | $0.0\text{\,}$ | $71.06\text{\,}$ | $28.65\text{\,}$ | $0.28\text{\,}$
jetbldr | $32,670\text{\,}$ | $2.99\text{\,}$ | $1,192.15\text{\,}$ | $-73.21\text{\,}$ | $11.41\text{\,}$ | $-12.45\text{\,}$ | $6.21\text{\,}$ | $12.67\text{\,}$ | $81.13\text{\,}$ | $66.96\text{\,}$ | $32.64\text{\,}$ | $0.4\text{\,}$
f1b | $16,716\text{\,}$ | $1.53\text{\,}$ | $1,251.63\text{\,}$ | $-12.39\text{\,}$ | $53.59\text{\,}$ | $-1.94\text{\,}$ | $16.72\text{\,}$ | $42.01\text{\,}$ | $41.27\text{\,}$ | $65.48\text{\,}$ | $34.03\text{\,}$ | $0.49\text{\,}$
Gambit Labs | $15,281\text{\,}$ | $1.4\text{\,}$ | $889.45\text{\,}$ | $-19.75\text{\,}$ | $78.42\text{\,}$ | $-4.03\text{\,}$ | $21.26\text{\,}$ | $24.72\text{\,}$ | $54.02\text{\,}$ | $57.41\text{\,}$ | $34.93\text{\,}$ | $7.66\text{\,}$
penguin | $14,622\text{\,}$ | $1.34\text{\,}$ | $1,028.28\text{\,}$ | $-41.77\text{\,}$ | $17.7\text{\,}$ | $-9.73\text{\,}$ | $11.8\text{\,}$ | $10.26\text{\,}$ | $77.94\text{\,}$ | $29.61\text{\,}$ | $66.7\text{\,}$ | $3.7\text{\,}$
tbuilder | $10,584\text{\,}$ | $0.97\text{\,}$ | $338.38\text{\,}$ | $-79.1\text{\,}$ | $-77.01\text{\,}$ | $-41.23\text{\,}$ | $0.44\text{\,}$ | $1.67\text{\,}$ | $97.88\text{\,}$ | $63.66\text{\,}$ | $36.07\text{\,}$ | $0.27\text{\,}$
lokibuilder | $5,609\text{\,}$ | $0.51\text{\,}$ | $253.18\text{\,}$ | $-10.52\text{\,}$ | $36.21\text{\,}$ | $-2.86\text{\,}$ | $23.28\text{\,}$ | $16.51\text{\,}$ | $60.21\text{\,}$ | $66.81\text{\,}$ | $32.13\text{\,}$ | $1.06\text{\,}$
BuildAI | $3,657\text{\,}$ | $0.33\text{\,}$ | $1,054.98\text{\,}$ | $0.0\text{\,}$ | $196.48\text{\,}$ | $13.49\text{\,}$ | $74.84\text{\,}$ | $25.16\text{\,}$ | $0.0\text{\,}$ | $83.31\text{\,}$ | $16.53\text{\,}$ | $0.16\text{\,}$
eden | $2,289\text{\,}$ | $0.21\text{\,}$ | $185.06\text{\,}$ | $0.0\text{\,}$ | $1.55\text{\,}$ | $2.0\text{\,}$ | $18.17\text{\,}$ | $81.83\text{\,}$ | $0.0\text{\,}$ | $66.08\text{\,}$ | $32.54\text{\,}$ | $1.38\text{\,}$
boba-builder | $2,126\text{\,}$ | $0.19\text{\,}$ | $412.33\text{\,}$ | $-2.6\text{\,}$ | $1.12\text{\,}$ | $-3.29\text{\,}$ | $26.76\text{\,}$ | $44.59\text{\,}$ | $28.65\text{\,}$ | $34.21\text{\,}$ | $21.25\text{\,}$ | $44.54\text{\,}$
eth-builder | $1,922\text{\,}$ | $0.18\text{\,}$ | $539.45\text{\,}$ | $-2.24\text{\,}$ | $159.71\text{\,}$ | $-11.67\text{\,}$ | $40.17\text{\,}$ | $31.53\text{\,}$ | $28.3\text{\,}$ | $59.87\text{\,}$ | $35.47\text{\,}$ | $4.66\text{\,}$
Beelder | $1,751\text{\,}$ | $0.16\text{\,}$ | $155.42\text{\,}$ | $0.0\text{\,}$ | $1.11\text{\,}$ | $1.2\text{\,}$ | $16.62\text{\,}$ | $83.38\text{\,}$ | $0.0\text{\,}$ | $79.24\text{\,}$ | $20.26\text{\,}$ | $0.5\text{\,}$
Anon:0x83bee | $1,631\text{\,}$ | $0.15\text{\,}$ | $1,519.58\text{\,}$ | $0.0\text{\,}$ | $427.16\text{\,}$ | $23.49\text{\,}$ | $100.0\text{\,}$ | $0.0\text{\,}$ | $0.0\text{\,}$ | $36.19\text{\,}$ | $54.33\text{\,}$ | $9.48\text{\,}$
bloXroute | $1,134\text{\,}$ | $0.1\text{\,}$ | $120.22\text{\,}$ | $-1.37\text{\,}$ | $1.84\text{\,}$ | $-6.42\text{\,}$ | $23.37\text{\,}$ | $35.19\text{\,}$ | $41.45\text{\,}$ | $68.87\text{\,}$ | $24.35\text{\,}$ | $6.78\text{\,}$
Anon:0xb3a6d | $997\text{\,}$ | $0.09\text{\,}$ | $974.33\text{\,}$ | $0.0\text{\,}$ | $215.69\text{\,}$ | $25.93\text{\,}$ | $98.4\text{\,}$ | $1.6\text{\,}$ | $0.0\text{\,}$ | $49.89\text{\,}$ | $45.92\text{\,}$ | $4.19\text{\,}$
BTCS | $955\text{\,}$ | $0.09\text{\,}$ | $19.59\text{\,}$ | $-8.97\text{\,}$ | $-8.9\text{\,}$ | $-226.95\text{\,}$ | $1.78\text{\,}$ | $5.55\text{\,}$ | $92.67\text{\,}$ | $53.76\text{\,}$ | $45.86\text{\,}$ | $0.38\text{\,}$
I can haz block? | $527\text{\,}$ | $0.05\text{\,}$ | $1,656.91\text{\,}$ | $-1.23\text{\,}$ | $1,094.65\text{\,}$ | $40.26\text{\,}$ | $97.34\text{\,}$ | $1.9\text{\,}$ | $0.76\text{\,}$ | $64.17\text{\,}$ | $35.54\text{\,}$ | $0.29\text{\,}$
payload | $426\text{\,}$ | $0.04\text{\,}$ | $312.69\text{\,}$ | $0.0\text{\,}$ | $14.23\text{\,}$ | $11.18\text{\,}$ | $56.1\text{\,}$ | $43.9\text{\,}$ | $0.0\text{\,}$ | $78.11\text{\,}$ | $20.23\text{\,}$ | $1.65\text{\,}$
bobTheBuilder | $408\text{\,}$ | $0.04\text{\,}$ | $130.09\text{\,}$ | $0.0\text{\,}$ | $49.11\text{\,}$ | $9.16\text{\,}$ | $44.12\text{\,}$ | $55.88\text{\,}$ | $0.0\text{\,}$ | $77.65\text{\,}$ | $21.69\text{\,}$ | $0.65\text{\,}$
lightspeedbuilder | $355\text{\,}$ | $0.03\text{\,}$ | $21.49\text{\,}$ | $-0.86\text{\,}$ | $-0.76\text{\,}$ | $-13.29\text{\,}$ | $1.41\text{\,}$ | $6.76\text{\,}$ | $91.83\text{\,}$ | $67.97\text{\,}$ | $30.86\text{\,}$ | $1.17\text{\,}$
EigenPhi | $343\text{\,}$ | $0.03\text{\,}$ | $19.75\text{\,}$ | $-0.0\text{\,}$ | $0.28\text{\,}$ | $3.07\text{\,}$ | $23.91\text{\,}$ | $75.8\text{\,}$ | $0.29\text{\,}$ | $66.77\text{\,}$ | $31.43\text{\,}$ | $1.8\text{\,}$
nfactorial | $335\text{\,}$ | $0.03\text{\,}$ | $112.33\text{\,}$ | $0.0\text{\,}$ | $63.27\text{\,}$ | $29.43\text{\,}$ | $97.31\text{\,}$ | $2.69\text{\,}$ | $0.0\text{\,}$ | $10.44\text{\,}$ | $83.24\text{\,}$ | $6.32\text{\,}$
smithbuilder | $330\text{\,}$ | $0.03\text{\,}$ | $22.12\text{\,}$ | $-0.64\text{\,}$ | $-0.65\text{\,}$ | $-12.34\text{\,}$ | $0.0\text{\,}$ | $10.61\text{\,}$ | $89.39\text{\,}$ | $53.23\text{\,}$ | $39.33\text{\,}$ | $7.43\text{\,}$
panda | $286\text{\,}$ | $0.03\text{\,}$ | $23.74\text{\,}$ | $-15.7\text{\,}$ | $-15.69\text{\,}$ | $-246.71\text{\,}$ | $0.35\text{\,}$ | $1.4\text{\,}$ | $98.25\text{\,}$ | $72.04\text{\,}$ | $27.5\text{\,}$ | $0.46\text{\,}$
Ty For The Block | $276\text{\,}$ | $0.03\text{\,}$ | $495.89\text{\,}$ | $-0.06\text{\,}$ | $788.55\text{\,}$ | $40.04\text{\,}$ | $94.2\text{\,}$ | $3.62\text{\,}$ | $2.17\text{\,}$ | $79.65\text{\,}$ | $19.5\text{\,}$ | $0.85\text{\,}$
antbuilder | $207\text{\,}$ | $0.02\text{\,}$ | $89.94\text{\,}$ | $-0.43\text{\,}$ | $2.27\text{\,}$ | $6.26\text{\,}$ | $64.73\text{\,}$ | $21.26\text{\,}$ | $14.01\text{\,}$ | $85.73\text{\,}$ | $14.04\text{\,}$ | $0.23\text{\,}$
merkle Block | $163\text{\,}$ | $0.01\text{\,}$ | $3.7\text{\,}$ | $-0.8\text{\,}$ | $-0.75\text{\,}$ | $-49.37\text{\,}$ | $0.61\text{\,}$ | $0.61\text{\,}$ | $98.77\text{\,}$ | $63.22\text{\,}$ | $35.99\text{\,}$ | $0.8\text{\,}$
ibuilder | $149\text{\,}$ | $0.01\text{\,}$ | $2.6\text{\,}$ | $-0.44\text{\,}$ | $-0.44\text{\,}$ | $-24.63\text{\,}$ | $0.0\text{\,}$ | $0.67\text{\,}$ | $99.33\text{\,}$ | $50.31\text{\,}$ | $49.17\text{\,}$ | $0.52\text{\,}$
s0e2t | $122\text{\,}$ | $0.01\text{\,}$ | $24.4\text{\,}$ | $0.0\text{\,}$ | $0.11\text{\,}$ | $1.43\text{\,}$ | $15.57\text{\,}$ | $84.43\text{\,}$ | $0.0\text{\,}$ | $22.79\text{\,}$ | $76.3\text{\,}$ | $0.91\text{\,}$
ashpool | $43\text{\,}$ | $0.0\text{\,}$ | $10.5\text{\,}$ | $0.0\text{\,}$ | $0.03\text{\,}$ | $1.02\text{\,}$ | $11.63\text{\,}$ | $88.37\text{\,}$ | $0.0\text{\,}$ | $59.24\text{\,}$ | $20.48\text{\,}$ | $20.28\text{\,}$
smithbot | $39\text{\,}$ | $0.0\text{\,}$ | $26.68\text{\,}$ | $0.0\text{\,}$ | $0.03\text{\,}$ | $-0.38\text{\,}$ | $28.21\text{\,}$ | $71.79\text{\,}$ | $0.0\text{\,}$ | $57.5\text{\,}$ | $40.95\text{\,}$ | $1.55\text{\,}$
If you build it, they will come. | $11\text{\,}$ | $0.0\text{\,}$ | $0.32\text{\,}$ | $0.0\text{\,}$ | $0.01\text{\,}$ | $4.73\text{\,}$ | $9.09\text{\,}$ | $90.91\text{\,}$ | $0.0\text{\,}$ | $43.72\text{\,}$ | $54.63\text{\,}$ | $1.65\text{\,}$
wenmerge | $3\text{\,}$ | $0.0\text{\,}$ | $0.28\text{\,}$ | $0.0\text{\,}$ | $0.0\text{\,}$ | $1.61\text{\,}$ | $0.0\text{\,}$ | $100.0\text{\,}$ | $0.0\text{\,}$ | $78.31\text{\,}$ | $21.63\text{\,}$ | $0.06\text{\,}$
Manifold | $2\text{\,}$ | $0.0\text{\,}$ | $0.15\text{\,}$ | $0.0\text{\,}$ | $0.09\text{\,}$ | $24.04\text{\,}$ | $50.0\text{\,}$ | $50.0\text{\,}$ | $0.0\text{\,}$ | $80.73\text{\,}$ | $19.18\text{\,}$ | $0.1\text{\,}$
Builder Boi | $2\text{\,}$ | $0.0\text{\,}$ | $0.04\text{\,}$ | $0.0\text{\,}$ | $-0.0\text{\,}$ | $0.0\text{\,}$ | $0.0\text{\,}$ | $100.0\text{\,}$ | $0.0\text{\,}$ | $83.47\text{\,}$ | $16.49\text{\,}$ | $0.04\text{\,}$
Table 5: Market Share, Profitability, and Block Packing Metrics of All
Builders

Figure 11: A horizontal bar plot indicating the share of value builders
receive from each transparency label. Builders on the y-axis are ordered in
ascending order based on their market share, with the builder with the highest
share listed at the bottom. Figure 12: A horizontal bar plot showing the share
of value builders receive from each order flow label. Builders on the y-axis
are ordered in ascending order based on their market share, with the builder
with the highest share listed at the bottom.

(a)

(b)

(c)

(d)

Figure 13: The significance of EOF providers. Figure 13(a) is an area plot
showing the trends in the share of value contributed by the seven most
prominent EOF providers based on total value. The total EOF value of the
remaining providers is aggregated and denoted as “Others” in the plot legend.
Figure 13(b), Figure 13(c), and Figure 13(d) are EOF provider area plots for
Titan, beaverbuild, and rysnc builders, respectively, with a dashed line plot
showing their cumulative profit in ETH on the right y-axis. The legend in
Figure 13(a) applies to all figures.  Figure 14: A horizontal bar plot showing
the share EOF value builders receive from providers. Builders on the y-axis
are ordered in ascending order based on their market share, with the builder
with the highest share listed at the bottom. Unknown providers are enumerated
according to [79].

| Total | Avg. | Avg. | Avg. | Total | Avg.
---|---|---|---|---|---|---
Builder | Blocks | Bids | Update Lag | Winner Time | Cancels | Cancels
| [#] | [#] | [ms] | [ms] | [#] | [#]
beaverbuild | $137,721\text{\,}$ | $31.54\text{\,}$ | $130.41\text{\,}$ | $586.59\text{\,}$ | $248,195\text{\,}$ | $1.74\text{\,}$
rsync | $95,310\text{\,}$ | $25.27\text{\,}$ | $166.21\text{\,}$ | $531.38\text{\,}$ | $212,504\text{\,}$ | $2.29\text{\,}$
Titan | $47,539\text{\,}$ | $31.11\text{\,}$ | $186.25\text{\,}$ | $605.83\text{\,}$ | $91,337\text{\,}$ | $1.78\text{\,}$
flashbots | $32,612\text{\,}$ | $16.25\text{\,}$ | $411.36\text{\,}$ | $348.45\text{\,}$ | $3,014\text{\,}$ | $0.1\text{\,}$
builder0x69 | $23,294\text{\,}$ | $20.64\text{\,}$ | $183.08\text{\,}$ | $575.09\text{\,}$ | $17,445\text{\,}$ | $0.65\text{\,}$
jetbldr | $12,960\text{\,}$ | $35.2\text{\,}$ | $103.08\text{\,}$ | $605.75\text{\,}$ | $904\text{\,}$ | $0.09\text{\,}$
Gambit Labs | $9,530\text{\,}$ | $15.85\text{\,}$ | $349.05\text{\,}$ | $496.3\text{\,}$ | $492\text{\,}$ | $0.1\text{\,}$
f1b | $9,242\text{\,}$ | $25.42\text{\,}$ | $214.18\text{\,}$ | $680.45\text{\,}$ | $10,494\text{\,}$ | $0.98\text{\,}$
penguin | $7,783\text{\,}$ | $49.64\text{\,}$ | $69.92\text{\,}$ | $652.91\text{\,}$ | $966\text{\,}$ | $0.13\text{\,}$
tbuilder | $4,786\text{\,}$ | $6.1\text{\,}$ | $476.68\text{\,}$ | $104.71\text{\,}$ | $81\text{\,}$ | $0.01\text{\,}$
lokibuilder | $3,445\text{\,}$ | $23.01\text{\,}$ | $200.14\text{\,}$ | $398.06\text{\,}$ | $1,176\text{\,}$ | $0.32\text{\,}$
BuildAI | $1,580\text{\,}$ | $7.39\text{\,}$ | $220.17\text{\,}$ | $511.55\text{\,}$ | $49\text{\,}$ | $0.03\text{\,}$
boba-builder | $1,048\text{\,}$ | $15.94\text{\,}$ | $531.17\text{\,}$ | $-530.01\text{\,}$ | $57\text{\,}$ | $0.04\text{\,}$
Beelder | $905\text{\,}$ | $1.96\text{\,}$ | $32.19\text{\,}$ | $383.65\text{\,}$ | $18\text{\,}$ | $0.03\text{\,}$
Anon:0x83bee | $753\text{\,}$ | $9.65\text{\,}$ | $462.65\text{\,}$ | $154.63\text{\,}$ | $34\text{\,}$ | $0.04\text{\,}$
eth-builder | $613\text{\,}$ | $4.81\text{\,}$ | $598.22\text{\,}$ | $454.77\text{\,}$ | $9\text{\,}$ | $0.02\text{\,}$
Anon:0xb3a6d | $452\text{\,}$ | $9.29\text{\,}$ | $645.09\text{\,}$ | $345.08\text{\,}$ | $93\text{\,}$ | $0.17\text{\,}$
I can haz block? | $317\text{\,}$ | $6.46\text{\,}$ | $1,007.86\text{\,}$ | $-828.63\text{\,}$ | $27\text{\,}$ | $0.04\text{\,}$
lightspeedbuilder | $269\text{\,}$ | $39.82\text{\,}$ | $70.68\text{\,}$ | $502.95\text{\,}$ | $1,472\text{\,}$ | $5.41\text{\,}$
eden | $262\text{\,}$ | $5.37\text{\,}$ | $486.39\text{\,}$ | $217.26\text{\,}$ | $227\text{\,}$ | $0.93\text{\,}$
payload | $210\text{\,}$ | $12.06\text{\,}$ | $482.52\text{\,}$ | $204.68\text{\,}$ | $62\text{\,}$ | $0.31\text{\,}$
bloXroute | $189\text{\,}$ | $10.8\text{\,}$ | $233.64\text{\,}$ | $342.44\text{\,}$ | $452\text{\,}$ | $0.68\text{\,}$
smithbuilder | $174\text{\,}$ | $27.29\text{\,}$ | $152.64\text{\,}$ | $529.19\text{\,}$ | $1,646\text{\,}$ | $6.12\text{\,}$
Ty For The Block | $173\text{\,}$ | $11.38\text{\,}$ | $579.5\text{\,}$ | $-291.24\text{\,}$ | $24\text{\,}$ | $0.15\text{\,}$
nfactorial | $163\text{\,}$ | $4.0\text{\,}$ | $814.76\text{\,}$ | $-527.05\text{\,}$ | $1\text{\,}$ | $0.0\text{\,}$
bobTheBuilder | $139\text{\,}$ | $3.01\text{\,}$ | $191.11\text{\,}$ | $733.85\text{\,}$ | $4\text{\,}$ | $0.03\text{\,}$
merkle Block | $127\text{\,}$ | $46.9\text{\,}$ | $114.19\text{\,}$ | $43.7\text{\,}$ | $331\text{\,}$ | $1.46\text{\,}$
antbuilder | $125\text{\,}$ | $59.51\text{\,}$ | $195.21\text{\,}$ | $588.75\text{\,}$ | $1,682\text{\,}$ | $10.21\text{\,}$
ibuilder | $48\text{\,}$ | $9.52\text{\,}$ | $499.84\text{\,}$ | $188.19\text{\,}$ | $3\text{\,}$ | $0.06\text{\,}$
ashpool | $26\text{\,}$ | $9.48\text{\,}$ | $231.43\text{\,}$ | $19.09\text{\,}$ | $3\text{\,}$ | $0.19\text{\,}$
s0e2t | $20\text{\,}$ | $1.6\text{\,}$ | $0.0\text{\,}$ | $150.5\text{\,}$ | $1\text{\,}$ | $0.02\text{\,}$
BTCS | $15\text{\,}$ | $22.98\text{\,}$ | $118.91\text{\,}$ | $-507.28\text{\,}$ | $40\text{\,}$ | $2.86\text{\,}$
EigenPhi | $8\text{\,}$ | $21.14\text{\,}$ | $654.98\text{\,}$ | $-1,367.5\text{\,}$ | $7\text{\,}$ | $1.16\text{\,}$
smithbot | $7\text{\,}$ | $10.83\text{\,}$ | $821.82\text{\,}$ | $470.75\text{\,}$ | $7\text{\,}$ | $0.58\text{\,}$
Manifold | $2\text{\,}$ | $41.0\text{\,}$ | $363.28\text{\,}$ | $568.5\text{\,}$ | $2\text{\,}$ | $1.0\text{\,}$
If you build it, they will come. | $1\text{\,}$ | $2.0\text{\,}$ | $431.0\text{\,}$ | $-3,981.0\text{\,}$ | $0\text{\,}$ | $0.0\text{\,}$
Table 6: Bidding and Latency Metrics of All Builders (UltraSound Relay)

| Excluded | Excluded | Excluded | Other Fee Payer | Promise Delivered | Over-Promised | Under-Promised | Relay
---|---|---|---|---|---|---|---|---
Builder | Blocks | Blocks | Value | Blocks | Blocks | Bid Value | Bid Value | Payment
| [#] | [%] | [ETH] | [%] | [%] | [ETH] | [ETH] | [ETH]
beaverbuild | $1,231.0\text{\,}$ | $0.3\text{\,}$ | $45.67\text{\,}$ | $5.08\text{\,}$ | $99.66\text{\,}$ | $92.8\text{\,}$ | $-14.0\text{\,}$ | $4.81\text{\,}$
rsync | $588.0\text{\,}$ | $0.21\text{\,}$ | $17.51\text{\,}$ | $1.88\text{\,}$ | $99.75\text{\,}$ | $55.93\text{\,}$ | $-5.88\text{\,}$ | $0.39\text{\,}$
Titan | $92,879.0\text{\,}$ | $34.3\text{\,}$ | $8,412.7\text{\,}$ | $7.35\text{\,}$ | $99.66\text{\,}$ | $55.27\text{\,}$ | $-4.72\text{\,}$ | $1.29\text{\,}$
flashbots | $108.0\text{\,}$ | $0.14\text{\,}$ | $3.31\text{\,}$ | $0.0\text{\,}$ | $99.03\text{\,}$ | $977.38\text{\,}$ | $-4.03\text{\,}$ | $0.0\text{\,}$
builder0x69 | $79.0\text{\,}$ | $0.22\text{\,}$ | $2.26\text{\,}$ | $0.0\text{\,}$ | $99.76\text{\,}$ | $3.7\text{\,}$ | $-0.38\text{\,}$ | $0.0\text{\,}$
jetbldr | $184.0\text{\,}$ | $0.56\text{\,}$ | $21.14\text{\,}$ | $1.57\text{\,}$ | $99.66\text{\,}$ | $0.94\text{\,}$ | $-1.05\text{\,}$ | $0.0\text{\,}$
f1b | $24.0\text{\,}$ | $0.14\text{\,}$ | $0.57\text{\,}$ | $0.0\text{\,}$ | $99.83\text{\,}$ | $3.3\text{\,}$ | $-0.13\text{\,}$ | $0.0\text{\,}$
Gambit Labs | $1,918.0\text{\,}$ | $11.15\text{\,}$ | $249.88\text{\,}$ | $0.0\text{\,}$ | $97.06\text{\,}$ | $416.15\text{\,}$ | $-0.24\text{\,}$ | $0.0\text{\,}$
penguin | $991.0\text{\,}$ | $6.35\text{\,}$ | $47.26\text{\,}$ | $0.01\text{\,}$ | $96.38\text{\,}$ | $3,470.56\text{\,}$ | $-0.22\text{\,}$ | $0.0\text{\,}$
tbuilder | $15.0\text{\,}$ | $0.14\text{\,}$ | $0.28\text{\,}$ | $0.0\text{\,}$ | $99.84\text{\,}$ | $0.11\text{\,}$ | $-0.06\text{\,}$ | $0.0\text{\,}$
lokibuilder | $13.0\text{\,}$ | $0.23\text{\,}$ | $0.26\text{\,}$ | $0.0\text{\,}$ | $99.72\text{\,}$ | $2.08\text{\,}$ | $-0.72\text{\,}$ | $0.0\text{\,}$
BuildAI | $5.0\text{\,}$ | $0.14\text{\,}$ | $0.1\text{\,}$ | $0.0\text{\,}$ | $99.75\text{\,}$ | $0.96\text{\,}$ | $-0.02\text{\,}$ | $0.0\text{\,}$
eden | $5.0\text{\,}$ | $0.22\text{\,}$ | $0.22\text{\,}$ | $0.0\text{\,}$ | $99.78\text{\,}$ | $0.13\text{\,}$ | $-0.02\text{\,}$ | $0.0\text{\,}$
boba-builder | $2.0\text{\,}$ | $0.09\text{\,}$ | $0.03\text{\,}$ | $0.0\text{\,}$ | $99.86\text{\,}$ | $0.09\text{\,}$ | $-0.06\text{\,}$ | $0.0\text{\,}$
eth-builder | $10.0\text{\,}$ | $0.52\text{\,}$ | $0.26\text{\,}$ | $0.0\text{\,}$ | $99.22\text{\,}$ | $0.65\text{\,}$ | $-0.02\text{\,}$ | $0.0\text{\,}$
Beelder | $3.0\text{\,}$ | $0.17\text{\,}$ | $0.08\text{\,}$ | $0.0\text{\,}$ | $99.49\text{\,}$ | $0.06\text{\,}$ | $-0.15\text{\,}$ | $0.0\text{\,}$
Anon:0x83bee | $2.0\text{\,}$ | $0.12\text{\,}$ | $0.05\text{\,}$ | $0.0\text{\,}$ | $99.69\text{\,}$ | $0.72\text{\,}$ | $-0.04\text{\,}$ | $0.0\text{\,}$
bloXroute | $1,598.0\text{\,}$ | $58.49\text{\,}$ | $245.56\text{\,}$ | $0.0\text{\,}$ | $99.38\text{\,}$ | $0.33\text{\,}$ | $-0.05\text{\,}$ | $0.0\text{\,}$
Anon:0xb3a6d | $0.0\text{\,}$ | $0.0\text{\,}$ | $0.0\text{\,}$ | $0.0\text{\,}$ | $100.0\text{\,}$ | $0.0\text{\,}$ | $0.0\text{\,}$ | $0.0\text{\,}$
BTCS | $7.0\text{\,}$ | $0.73\text{\,}$ | $0.22\text{\,}$ | $0.0\text{\,}$ | $97.61\text{\,}$ | $0.11\text{\,}$ | $-0.26\text{\,}$ | $0.0\text{\,}$
I can haz block? | $0.0\text{\,}$ | $0.0\text{\,}$ | $0.0\text{\,}$ | $0.0\text{\,}$ | $100.0\text{\,}$ | $0.0\text{\,}$ | $0.0\text{\,}$ | $0.0\text{\,}$
payload | $1.0\text{\,}$ | $0.23\text{\,}$ | $0.02\text{\,}$ | $0.0\text{\,}$ | $99.53\text{\,}$ | $0.01\text{\,}$ | $0.0\text{\,}$ | $0.0\text{\,}$
bobTheBuilder | $0.0\text{\,}$ | $0.0\text{\,}$ | $0.0\text{\,}$ | $0.0\text{\,}$ | $100.0\text{\,}$ | $0.0\text{\,}$ | $0.0\text{\,}$ | $0.0\text{\,}$
lightspeedbuilder | $28.0\text{\,}$ | $7.31\text{\,}$ | $7.18\text{\,}$ | $0.0\text{\,}$ | $99.74\text{\,}$ | $0.18\text{\,}$ | $0.0\text{\,}$ | $0.0\text{\,}$
EigenPhi | $0.0\text{\,}$ | $0.0\text{\,}$ | $0.0\text{\,}$ | $0.0\text{\,}$ | $100.0\text{\,}$ | $0.0\text{\,}$ | $0.0\text{\,}$ | $0.0\text{\,}$
nfactorial | $1.0\text{\,}$ | $0.3\text{\,}$ | $0.02\text{\,}$ | $0.0\text{\,}$ | $99.7\text{\,}$ | $0.05\text{\,}$ | $0.0\text{\,}$ | $0.0\text{\,}$
smithbuilder | $0.0\text{\,}$ | $0.0\text{\,}$ | $0.0\text{\,}$ | $0.0\text{\,}$ | $100.0\text{\,}$ | $0.0\text{\,}$ | $0.0\text{\,}$ | $0.0\text{\,}$
panda | $0.0\text{\,}$ | $0.0\text{\,}$ | $0.0\text{\,}$ | $0.0\text{\,}$ | $100.0\text{\,}$ | $0.0\text{\,}$ | $0.0\text{\,}$ | $0.0\text{\,}$
Ty For The Block | $1.0\text{\,}$ | $0.36\text{\,}$ | $0.02\text{\,}$ | $0.0\text{\,}$ | $99.64\text{\,}$ | $0.08\text{\,}$ | $0.0\text{\,}$ | $0.0\text{\,}$
antbuilder | $2.0\text{\,}$ | $0.96\text{\,}$ | $0.05\text{\,}$ | $0.0\text{\,}$ | $99.04\text{\,}$ | $0.59\text{\,}$ | $0.0\text{\,}$ | $0.0\text{\,}$
merkle Block | $0.0\text{\,}$ | $0.0\text{\,}$ | $0.0\text{\,}$ | $0.0\text{\,}$ | $100.0\text{\,}$ | $0.0\text{\,}$ | $0.0\text{\,}$ | $0.0\text{\,}$
ibuilder | $0.0\text{\,}$ | $0.0\text{\,}$ | $0.0\text{\,}$ | $0.0\text{\,}$ | $100.0\text{\,}$ | $0.0\text{\,}$ | $0.0\text{\,}$ | $0.0\text{\,}$
s0e2t | $1.0\text{\,}$ | $0.81\text{\,}$ | $0.03\text{\,}$ | $0.0\text{\,}$ | $99.19\text{\,}$ | $0.14\text{\,}$ | $0.0\text{\,}$ | $0.0\text{\,}$
ashpool | $0.0\text{\,}$ | $0.0\text{\,}$ | $0.0\text{\,}$ | $0.0\text{\,}$ | $100.0\text{\,}$ | $0.0\text{\,}$ | $0.0\text{\,}$ | $0.0\text{\,}$
smithbot | $2.0\text{\,}$ | $4.88\text{\,}$ | $0.06\text{\,}$ | $0.0\text{\,}$ | $92.68\text{\,}$ | $0.02\text{\,}$ | $-0.07\text{\,}$ | $0.0\text{\,}$
If you build it, they will come. | $0.0\text{\,}$ | $0.0\text{\,}$ | $0.0\text{\,}$ | $0.0\text{\,}$ | $100.0\text{\,}$ | $0.0\text{\,}$ | $0.0\text{\,}$ | $0.0\text{\,}$
wenmerge | $0.0\text{\,}$ | $0.0\text{\,}$ | $0.0\text{\,}$ | $0.0\text{\,}$ | $100.0\text{\,}$ | $0.0\text{\,}$ | $0.0\text{\,}$ | $0.0\text{\,}$
Manifold | $320.0\text{\,}$ | $99.38\text{\,}$ | $12.65\text{\,}$ | $0.0\text{\,}$ | $91.61\text{\,}$ | $0.22\text{\,}$ | $-2.26\text{\,}$ | $0.0\text{\,}$
Builder Boi | $0.0\text{\,}$ | $0.0\text{\,}$ | $0.0\text{\,}$ | $0.0\text{\,}$ | $100.0\text{\,}$ | $0.0\text{\,}$ | $0.0\text{\,}$ | $0.0\text{\,}$
Table 7: Validator Payment Metrics of All Builders