Policy on Bitcoin Hardforks (Update) and SegWit2x (B2X)

Anyone can create a chain fork of Bitcoin at any time. The possibility of a SegWit2x hardfork (B2X) in November 2017 requires that we, once again, clarify our position on any and all potential hardforks.


BitMEX Hardfork Policies

At BitMEX, our top priority is protecting the assets of our customers. In order for us to effectively do this, we insist that any Bitcoin hardfork includes the following:

  • Strong two way transaction replay protection, enabled by default, such that transactions on each chain are invalid on the other chain.
  • A clean break, such that the new chain cannot be “wiped out” by the original chain.
  • A modification to the block header, such that all wallets (including light clients) are required to upgrade to follow the hardforked chain.
  • A change in address format, to prevent people inadvertently sending coins to an address on the wrong chain.
  • New P2P network magic, to ensure a functioning and reliable node network for both coins.

Strong replay protection and wipeout protection, in particular, are considered absolutely crucial.  Should a hardfork not follow these policies, we will not support the new coin. To be clear, we do not intend to access or keep these coins. The administrative overhead of distributing any and all hardforked coins (including Bitcoin-based distributions like Byteball/Lumens) is prohibitive and BitMEX will not monitor or maintain balances of hard-forked coins.

Additionally, support of any forked currency is solely at the discretion of BitMEX. While we may snap users’ margin balances at the time of the fork in case we decide to distribute, there is no guarantee that it will be safe, desirable, or practical to do so. If this concerns you, you should withdraw your funds before any given fork and handle the split on your own.


SegWit2x (B2X) – BitMEX Policy

The SegWit2x (B2X) proposal is aimed at increasing the blocksize. It is scheduled to take place in November 2017. This change is incompatible with the current Bitcoin ruleset and therefore a new coin may be created.  

Proponents of this new coin hope it becomes known as Bitcoin, however which coin is known as Bitcoin is not up to the proponents of the new token. Investors and traders may decide which coin has the highest value.  In order for this process to work smoothly, strong two way  transaction replay protection is necessary.

It is our understanding that the SegWit2x proposal does not include two way transaction replay protection, enabled by default. Therefore BitMEX will not be able to support SegWit2x.

As such, BitMEX will not support the distribution of B2X, nor will BitMEX be liable for any B2X sent to us.  This policy applies even if the SegWit2x chain has the majority hashrate. Therefore, it is up to our users to withdraw their Bitcoin’s from BitMEX prior to the fork if they wish to access B2X.

BitMEX considers any and all contentious hardfork tokens as altcoins. The .BXBT and .BXBTJPY indices will remain unchanged and will not include B2X.

The SegWit2x (B2X) Hardfork – Protecting Yourself and Your Coins, Part 1: Coin Splitting

Abstract: The upcoming SegWit2x hardfork lacks replay protection.  In this piece we look at what you can do to protect yourself, by analyzing various ways you could split your coins.



SegWit2x (B2X) is a proposal to double Bitcoin’s capacity limit. This is an increase in the maximum block weight to 8MB from 4MB.

The upgrade is an incompatible with Bitcoin’s current consensus rules (known as a hardfork), which means it is likely to result in a new coin, such that Bitcoin holders prior to the fork will receive both original Bitcoin (BTC) and SegWit2x coin (B2X) after the fork. In many ways this is similar to the recent Bitcoin Cash hardfork (also an increase in the blocksize limit to 8MB). A key difference is that unlike Bitcoin Cash, B2X does not include strong transaction replay protection. Therefore many users could lose funds, on the other hand, those that do successfully protect their funds could make positive investment returns.

The hardfork is expected to occur on around Saturday 18th November 2017. (Block number 494,784)


Why bother splitting?

The SegWit2x split will result in two coins, the existing Bitcoin (BTC) and a new “spin-off” coin SegWit2x (B2X). This is likely to lead to significant price volatility, which may present investment opportunities. Due to the lack of replay protection, whatever your view on the situation or your investment strategy, it is sensible to split your coins as soon as possible, to ensure as much flexibility as possible and also to protect your coins.  Many users are likely to intend to send only one of the two coins in a transaction, but accidentally send both, which may result in an irrecoverable loss of funds.  If you do not split, you could be one of these users incurring losses.

Unfortunately the lack of strong replay protection may also present an opportunity for scammers/attackers. For example scammers could repeatedly deposit and withdraw from exchanges, hoping to find any weaknesses. If any exchange has not implemented replay protection, attackers are likely to exploit this quickly, which could make the exchange insolvent. In addition to this, individual users could be targeted by scammers. Scammers could sell the victim Bitcoin, knowing their wallet is following the wrong chain or scammers could acquire Bitcoin from a victim who is expected to replay coins on both chains to the buyer.

These kind of losses and attacks could damage the reputation of the ecosystem, therefore a contentious hardfork without strong replay protection is a high risk event with potentially significant negative consequences. However, there are actions you can take to protect yourself.


Splitting your coins

When the hardfork occurs, your Bitcoin will exist separately on both chains BTC & B2X, in the same output. Since the B2X hardfork does not contain transaction replay protection enabled by default, when spending your coins, in either chain, the transaction could be replayed on the other chain.  Therefore the prudent thing to do is split your coins, so that your BTC and B2X exist on different outputs on each chain, which means that your transactions can no longer be replayed.

Unfortunately this is not a simple process and many people are unlikely to be able to achieve this. You cannot split your coins prior to the hardfork, however a prudent strategy may be to prepare how you plan to split beforehand, for example moving your coins to a different wallet before the fork occurs. For many users this is not likely to be easy, however if you act fast, there could be investment rewards, if you are able to sell the spin-off coin before others have a chance to do so.


Which wallets to use

In order to split your coins, you would either need to manually construct your own transactions or use two wallets, one for BTC and one for B2X, since most wallets will not allow you to broadcast two conflicting transactions. You will then need two separate wallets, to receive the coins on each side of the split.

Unfortunately two full node wallets are likely to be necessary to protect your coins, for example Bitcoin Core for BTC and BTC1 for B2X. A full node wallet means it verifies all the consensus rules on the entire blockchain. Two fully verifying nodes may be needed because:

  • On the BTC side you may need a wallet that enforces the 4 million unit weight limit (which B2X plans to breach), and;
  • On the B2X side you need a wallet that enforces the coin wipeout protection rule, which requires non witness data in the first B2X block to be greater than 1MB.

You need to ensure each respective wallet enforces each of these rules, to make sure your wallets do not follow a different chain to the one on which your coins are located on.  Otherwise your coins could disappear from your wallet.

In order to prudently prepare for the hardfork, it might be a good idea to run full nodes of each client on a separate computer. The syncing process can take several days, therefore perhaps you could start to run the nodes before the fork, as you may want to be ready to split your coins and spend them as soon as possible.


The splitting methods

Method 1: The trial and error approach

The most basic way of splitting is to run a BTC client and a B2X client, import your private keys, and then try to send your coins to yourself, to two different outputs on each chain. Either both transactions confirm, in which case you succeeded, or the same transaction occurs on both chains, and you simply try again.

The trouble with this method is that it could be expensive, in terms of both time and money. Many people may try this approach and therefore network congestion could be high, and the more failed attempts occur the more one needs to pay in fees. In addition to this, at least one of the two chains is guaranteed have minority hashpower, which could increase the block interval in the short term, resulting in more transaction congestion and you would need to wait for your transaction to confirm on both sides of the split to ensure you are protected.

Unfortunately, the trouble with B2X, is not only did this fork not implement strong replay protection, so that BTC transactions are valid on B2X and vica versa, but B2X also uses the same network magic as BTC. Therefore, by default your B2X wallet will broadcast its transactions to the BTC network, making transaction replay likely.


Method 2: Locktime

Locktime is a transaction field, which ensures a transaction is only valid after a certain block height. By default some wallets, including Bitcoin Core, add the current block height to the locktime field for their transactions. There are several motivations for this transaction type, one of which is to reduce the incentive for miners to orphan the current leading block, in order to get more fee income, by scooping up the fees from transactions already confirmed in the last block and the transactions in the memory pool. This is expected to be a potential problem in the future when the block reward is low.

One could try to use this feature to split BTC and B2X coins. For example, if the BTC chain has a 5 block lead over the B2X chain, you could send a BTC transaction with the current block height as the locktime, therefore this transaction will be invalid on B2X for the next 5 blocks. If the transaction confirms on BTC, you could then send another different transaction spending the same output on the B2X network, before the 5 block period is over. This could also work the other way around if B2X has the block height lead.

This method sounds complicated, and involves monitoring both chains. However, using the Bitcoin Core wallet this may happen by default and can be combined with the trial and error method described above. In theory, all you need to do is see which chain is in the lead, with respect to block height, and then send your transaction on that chain first.


Method 3: The “official” opt in replay protection

The B2X chain is considering adding opt in replay protection. This essentially means B2X client defines a subset of existing valid transactions and then prohibits these transactions on the B2X chain. Therefore you could send a transaction in this format on the BTC network and it would be invalid on B2X, resulting in a successful split.

However, this could be technically challenging to do, as it is not clear if any BTC wallets will support this feature and there may not be enough time for wallets to implement this for ordinary users. In addition to this, it is not known what type of opt in replay protection B2X will use or if this feature will be enabled at all. The official B2X client appears to have gone through the following iterations:

  • Initially there was no opt in transaction replay protection
  • A method of replay protection using OP_Return was merged into the codebase
  • A new replay protection method, banning transactions with an output to a particular P2SH address was merged
  • Problems were found with the latest method, which could apparently result in the loss of funds. Therefore a few days ago this opt in replay protection was removed from the B2X client

Therefore it is not clear what the opt in replay protection for B2X will be and it’s possible there could be no option here at all.


Method 4: Taint the coins with already split coins

Somebody else may have successfully been able to split their coins. They could then send you an output from their split coins. You could then use this output as an input for your new transaction. Since this input only exists on one chain, your transaction would be invalid on the other chain. Ideally this could be the coinbase reward from a block mined after the split, that way you can be sure your transaction can only occur on one side of the split, regardless of any potential re-orgs.

This process seems easier than the above methods, although you must ensure you get your coin control in your wallet arranged correctly to ensure you spend the desired transaction input. This method requires waiting for somebody else, therefore it could be slow, which may be a problem if you want to split as soon as possible.


Method 5: Let an exchange do it

You could send your coins to an exchange which supports both BTC and B2X, the exchange could then handle the split for you. You need to check if the policy of the exchange is to split your coins before the split or to also split coins sent to them after the split.

A disadvantage of this policy is that your need to take counterparty risk, which you may not want to do with your long term savings.  Taking such a risk could be particularly problematic during a high risk, high volume period such as a chain split without strong replay protection, which may present operational challenges for the exchanges. This method also goes against a common narrative or mantra in the Bitcoin community, which is you should always control your private keys, especially during a hardfork.

Although an advantage of sending your coins to the exchange before the fork, is that you may be able to trade the two coins very quickly, perhaps even faster than those doing the above split methods. This could provide you better investment opportunities.



Perhaps the best strategy is to combine the above methods. After reviewing the policy of the exchanges, you could send some of your coins to an exchange of your choice before the fork and then attempt to split the remainder of your coins using method 2 explained above.

However, despite all this advice, it’s probably likely that the overwhelming majority of Bitcoin holders will take no preparatory action for the split. Therefore if you do any above, you are probably well ahead of the majority, which could hopefully lead to some financial rewards or at least help you avoid losses.

The SegWit2x (B2X) Hardfork – Protecting Yourself and Your Coins, Part 2: Investment Strategies

Abstract: The upcoming SegWit2x hardfork is likely to lead to price volatility.  In this piece we look at some potential investment strategies which could allow you to capitalize on the event.


Strategy 1: Do nothing

The most popular investment strategy following the split is likely to be to take no action and remain a holder of both BTC and B2X. This is probably the most prudent approach, as your assets may be protected whichever coin becomes more valuable. Most people may pursue this strategy out of laziness rather than choice.  However, even if this is your preferred investment strategy, it may still be sensible to try and split your coins anyway; to increase the flexibility of your investment strategy and protect your funds in case you need to make a transaction.


Strategy 2: Invest in your favored coin

Many investors may support either the BTC or B2X coin for ideological reasons or because they feel their chosen coin has the best characteristics.

  • Supporters of BTC typically prefer the consensus rules to be robust, as they feel this results in superior or more unique monetary characteristics. Also they typically value the cautious and meticulous approach of the current development team. BTC supporters may want flexibility and innovation to come from other layers in the system above the consensus rule layer.
  • In contrast to this B2X supporters may value a more flexible consensus ruleset to ensure the system is dynamic and able to cater to user requirements more quickly. B2X supporters typically value the user experience over the monetary characteristics of the system. Typically they draw less distinction between changes in the consensus layer and other types of changes to the system.

If you agree with one of these visions more than the other, it might be a good idea to invest in the coin that matches your vision, this may not only help you obtain larger returns if your vision is correct, but may also help ensure your favoured token is the “winner”, as it may contribute to the value of the coin.

Alternatively you may not care which vision “wins”, but want to back the winner. In this case it’s important not just to gage opinion, but also the level of conviction those on each side of the debate have. Somebody slightly favouring one of the visions but also wanting to hedge their bets may have less of an impact than a die hard supporter of one of the visions, who is willing to sell all their coins on one side of the split no matter what. This factor could favor the BTC side, since many die hard “large blockers” may have already sold some BTC to invest in Bitcoin Cash.

The most common investment strategy after the fork may be to do nothing. However, of the tiny minority of people that do act, many of those people may be sellers of B2X. This is because the section of the minority that took action in favor of the large block chain in August, will not be allocated either BTC or B2X for the coins they sold for Bitcoin Cash. In contrast, the minority that quickly sold Bitcoin Cash in August, will be allocated BTC and B2X this November. Although, obviously this is highly speculative and nobody really knows what will happen.


Strategy 3: Invest in whichever coin is the cheapest/the “bad” coin – The Joel Greenblatt strategy

The top investment tip in one of our favorite books on investing, Joel Greenblatt’s “You can be a stock market genius” (bad title but a great read), appears to be that if a stock split occurs, one should buy the less favored company, the spin-off.  In this case B2X is the spin-off token.

Joel Greenblatt’s Gotham Capital achieved annualized investment returns of 50% from 1985 to 1994. One of the core strategies of the fund in this period was to invest in “bad” spin-off companies. As Greenblatt explains:

There are plenty of reasons why a company might choose to unload or otherwise separate itself from the fortunes of the business to be spun off. There is really only one reason to pay attention when they do: you can make a hole of money investing in spin-offs. The facts are overwhelming. Stock of spin-off companies, and even shares of the parent companies that do then spinning off, significantly and consistently outperform the market averages. One study completed at Penn State, covering a twenty five year period ending 1988, found that stocks of spin-off companies outperformed their industry peers and the S&P 500 by about 10% per year in their first three years of independence.

Greenblatt mentions that spin-offs tend to be driven by a “desire to separate out a bad business so that an unfettered good business can show through to investors”. The bad company or spin-off company is typically sold by investors, with the negative narrative around the bad company dominant at the time of the split, causing negative sentiment. As Greenblatt explains:

The spin-off process itself is a fundamentally inefficient method of distributing stock to the wrong people. Generally, the new spin-off stock isn’t sold, its given to shareholders who, for the most part, were investing in the parent company’s business. Therefore, once the spin-off’s shares are distributed to the parent company’s shareholders, they are typically sold immediately without regard to the price of fundamental value. The initial excess supply has a predictable effect on the spin-off stock’s price: it is usually depressed. Supposedly shrewd institutional investors also join in the selling. Most of the time spin-off companies are much smaller than the parent company. A spin-off may be only 10 or 20 percent the size of the parent. Even if a pension or mutual fund took the time the analyze the spin-off’s business, often the size of these companies is too small for an institutional portfolio.

Greenblatt goes on to cite four spin off case studies, Host Marriott/Marriott International, Strategic Security/Briggs & Stratton, American Express/Lehman Brothers and Sears/Dean Witter, where this thesis applied.

In many ways there are some analogies between the opportunities which may arise from Bitcoin spin-offs such as B2X and stock spin-offs. Perhaps B2X is being distributed to the “wrong people”. Bitcoin investors typically value robust rules and the resulting highly resilient monetary properties. Perhaps, some of the Bitcoin investors who value other characteristics such as flexibility and user experience may have already divested into Ethereum or Bitcoin Cash, therefore the remaining investors may “dump” B2X. The risk for B2X proponents is they allocate their new coin to the “wrong people” and the price becomes “depressed”.  However, this could provide contrarian investors an opportunity.

The price of B2X could fall to cheap levels and there could be significant amounts of negative sentiment with some people writing the coin off. This could then be a good time for contrarians to invest in B2X. This investment philosophy seems to go against a common narrative in the Bitcoin space that “network effect is king” or “the most work chain wins”, meaning a minority chain has limited prospects. However, there may be little investment basis for this view.

However, whether the Greenblatt spin-off philosophy really applies to Bitcoin spin-offs such as B2X is not clear. Greenblatt still does fundamental analysis on the bad spin-off company, and whether one can take this type of fundamental approach to Bitcoin or its spin-offs, is not obvious. It’s certainly more risky. Although, in my view, after the hardfork, if B2X is trading at c5% or less of the price of Bitcoin and the prevailing narrative is that B2X is dead, then the “bad” coin may be worth a small punt.


Strategy 4: Take advantage of different policies on different exchanges

During the Bitcoin Cash hardfork, different financial platforms had different policies. For example BitMEX essentially ignored Bitcoin Cash, and the futures price just followed Bitcoin. However, Kraken for example, supported Bitcoin Cash, in such a way that those with long margin positions on Bitcoin were also given Bitcoin Cash. Critically on Kraken if you were short Bitcoin at the time of the fork, you were then automatically short Bitcoin Cash. These different policies between exchanges provide asymmetry, which in theory can be used to earn free money.

For example going into the Bitcoin Cash hardfork, an interesting strategy was to open a margin long position of 1 BTC on Kraken and then hedge the position by taking a margin short position of 1 BTC on BitMEX. Thereby after the hardfork, you receive one Bitcoin Cash token on Kraken, essentially for free, since there was no corresponding Bitcoin Cash liability on BitMEX associated with the short.

When it comes to the upcoming fork, there are four relevant potential exchange policies one needs to consider, when trying to engage in this type of arbitrage.


Potential financial platform policies regarding the B2X spin-off token

Policy A Policy B Policy C Policy D
Split user Bitcoin deposit balances into BTC & B2X
Split user Bitcoin margin long positions into BTC & B2X long positions
Split user Bitcoin margin short positions into BTC & B2X short positions
Bitcoin lenders are due back BTC & B2X
Bitcoin borrowers owe BTC & B2X  

Note: It is also possible to have a different policy with respect to Bitcoin lending and Bitcoin margin positions, which is not illustrated in the above chart.

An interesting investment strategy to engage in before the B2X fork could be to open long Bitcoin positions with exchanges with policy C and D, and potentially open short Bitcoin positions on exchanges with policies A, B and C.  In theory, this should allow you to get B2X tokens for free.

One may think that policy C may seem a slightly inappropriate choice, as it results in an asymmetry. However some exchanges did have a policy similar to this with respect to Bitcoin Cash. The rational for this was that the burden on customers who were short Bitcoin, to go out into the market and buy Bitcoin Cash may have been too high, particularly if the liquidity of Bitcoin Cash was low.

As the B2X fork approaches, we may write a piece summarizing the policies of the main exchanges and how one could engage in this type strategy. Although, if you wait for it to be clearly explained, it could be too late and spreads could have already opened up, reflecting the opportunity. On Bitfinex, B2X is already trading at over $1,000, therefore there could be money to be made by engaging in these types of strategies. Perhaps a good idea, if you really like taking risks, may be to review the policies exchanges took with respect to Bitcoin Cash, to get an idea of what their policies might be with respect to B2X and then open your positions before the policies are officially announced.

ICO – 第二部分 - 投资回报




资料来源:BitMEX 研究,Coinmarketcap,ICO网站,Reddit评论




  • 一般来说,ICO价格的数据质量很差,在许多情况下可能会出现重大计算错误。对于任何不准确之处,我们深表歉意。
  • ICO项目通常具有其自身独特的情况和条件,例如ICO融资次数的不同或以及用不同加密货币来进行融资。不幸的是,由于缺乏透明度和高度的复杂性,在某些情况下,我们无法保持所有项目的自身特性的一致性。
  • 在某些情况下,我们可能无法确定ICO价格,因此使用其在第一天的交易价格 。
  • 在我们的分析中可能会存在一些选样偏差,例如,我们的调查样板中可能偏向一些后期投资表现较成功的ICO项目。
  • 不幸的是,在少数情况下,由于缺乏替代资料,我们采用了Reddit评论中的 ICO价格。


资料来源:BitMEX 研究,Coinmarketcap,ICO网站,Reddit评论,Coindesk






资料来源:BitMEX研究,Coinmarketcap,ICO网站,Reddit评论,ICO Hunt






BitMEX (www.bitmex.com)

ICO – 第一部分 - ICO团队成员/顾问间的互动关系网




资料來源:BitMEX 研究,ICO网站,icoHunt自己提供原始数据(未经许可不得使用)



  • 蓝圈代表ICO
  • 黄色圈子代表ICO团队成员,顾问或支持者
  • 圆圈的大小是根据其他ICO的加权链接数量
  • 数据包括500个ICO和c5,000个团队成员
  • 对于任何资料的错误,遗漏或拼写失误,我们深表歉意


  • 将节点数修改为1000左右
  • 从5个节点开始,然后逐渐按向上箭头一次添加10个节点
  • 显示所有5,388个节点可能会占用大量的系统资源
  • 这里提供了可图像化类型的演示


上图显示的关系网说明了ICO之间的联系是非常紧密的,少数人参与了众多的项目 。因此,批评者可能会认为一个人不应该参与这么多的ICO项目中,这现象也表现出误导营销,不良做法和披露不充分等问题。



许多ICO项目中列出的参与人均为项目支持者或顾问,而不是作为项目日常管理人。在某些方面来看,他们更多的是ICO项目的“保荐人”,而不是积极参与项目的管理者或开发人员。例如,如下图所示,涉及多个ICO项目的个人集中度与参与IPO的财务顾问或簿记管理人的集中度非常吻合。Vitalik Buterin是参与ICO项目最多的人物。我们的分析显示,他至少参与了13个项目,占总数的2.5%左右。就算Vitalik所扮演的是保荐人的角色,那么Vitalik所占的市场份额要比花旗银行在IPO上所占的市场份额要低,花旗银行过去12个月中所占的市场份额为3.7%。


财务顾问市场份额分布(前20名) –  ICO / IPO比较

资料来源:BitMEX 研究,icoHunt,ICO网站,Bloomberg IPO数据库




  • 承销所发行的上市公司股票,
  • 确保股票上市后的价格稳定性和流动性,
  • 准备上市股票发行营销材料,
  • 安排公司的管理层与路演中的潜在投资者接洽,
  • 利用销售人员通过电话和电子邮件向客户推销上市公司股票,
  • 协助向参与者分配发行股份比例。

在许多方面,这些责任与上述ICO项目中一些最突出的参与者的角色类似,特别在项目推广和营销方面。然而,在ICO世界,“保荐人”的作用更加模糊。有时发起这个想法的人,也参与管理甚至负责项目的开发。 ICO的市场中对个人所担任的角色和责任缺乏明确性。



上市期间股份的初始分配过程通常是不透明的 。通常,财务顾问会“酌情”分配,大型机构和对冲基金客户首先受惠,而不是透过公平的随机分配或拍卖机制。金融监管机构对于这种做法尽然不进行规管,这还是有点令人惊讶。虽然有关监管的反对者认为上市公司应该有自由决定自己新股东是谁,如果投标人很多的话。不幸的是,这名簿记管理人/财务顾问似乎在这个过程中有着很大的影响力。

尽管有机会改善IPO在这方面的运作模式,但是对于ICO初始分配过程而言, 似乎并不比IPO好到哪去。ICO的初始分配过程也是不明确的,甚至在某些方面比IPO更糟,因为早期投资者或关系户投资者往往可以以较低的价格参与ICO项目。其分配过程是根据谁是项目团队的好哥们儿或谁拥有更好行业关系 。因此,尽管IPO的运作方式不佳,但IPO似乎在初始分配方面比ICO更公平一些。




BitMEX (www.bitmex.com)

SegWit交易容量增长 – 第二部分 – 激活后的第一个月





图1 – 交易费用与SegWit的应用规模

资料来源: BitMEX 研究部
注脚: 数据为日平均,至2017年9月20日


如下图2所示,以比特币计价交易费用与比特币价格和比特币价格波动有关。这种关系可能是由于比特币价格上涨导致交易需求增加。 SegWit激活后的第一个月是比特币大幅上涨和价格波动较大的时期,这使得交易费用下调看起来有些不寻常。这个交易费用下降是在价格仍在迅速上涨的时期发生的 。


图2  – 交易费用与比特币价格

资料来源: BitMEX 研究部
注脚: 数据为日平均,至2017年9月20日




图3 – SegWit应用数量与旧交易模式相比

资料来源: BitMEX 研究部
注脚: 数据为日平均,至2017年9月20日





BitMEX (www.bitmex.com)

SegWit交易容量增长 – 第一部分

摘要:SegWit以新的较复杂的400万单位区块容量取代了原来的1MB的区块大小限制 。在钱包升级成SegWit 的交易格式后,这将令到网络交易量提升两倍 。本文章主要分析在随着用户逐渐更新并使用 SegWit交易的情况下,如何提升网络交易量。



隔离见证Segregated Witness简称SegWit是比特币制式的升级,该可能会增加整体网络交易量。用户需要先升级到新的交易格式,才能受益于高交易量的提升。这可能会使整体交易量以一个缓慢而逐渐的方式提升。尽管那些升级的人可以立马得到交易费用减少的好处。




4 * non witness data (in bytes) + witness data (in bytes) < 4 million units



见证数据(Witness Data)是什么?



SegWit – 交易构的明(百分比数据占用)


SegWit– 交易构的明(百分比数据占用)








不升级到SegWit的用户的交易费用应该与之前维持相同水平。但是,由于其他用户使用SegWit而释放了部分的固有容量,理论上他们可能会感受到“附属效益”。该效益可能会改善市场收费情况并降低交易费用,即使对于尚未升级到SegWit的用户。估计这个所谓的“附属效益”的规模几乎是不可能的,因为这取决于整体市场收费的情况 。












在右侧的图表显示,理论上一个区块的大小(在只包含见证数据的情况下)可以达到 4MB,垃圾区块制造者可能产生与生成1MB区块(只包含非见证数据)相同的费用。由于两个区块都拥有400万个单位。










  1. 签名认证:通过更改交易哈希中签名的计算,使得每笔交易的每个字节只需要最多运算两次,SegWit减轻了二次运算的签名哈希操作问题。因此,包含大量见证数据的区块将包含大量有线性特征的数据,减少了潜在的签名验证时间并提高了可扩展性。
  2. 数据库对未使用的交易输出(UTXO)的影响:见证数据涉及交易输入的签名。如果只想创建新的交易输出数据,则将不会被包含在见证数据中。因此,理论上4MB区块不包含新的输出数据。因此,大区块对UTXO集的大小具有中立或甚至正面的影响。
  3. 长期存储成本:最糟糕的情况是4MB块可能对长期存储成本产生负面影响。然而,当采用隔离认证时,计算交易ID(TXID)的过程便不再需要认证数据。这意味着可以在计算TXID,梅克尔树根哈希和区块哈希时,不再需要见证数据。所需要的只是见证承诺以及可以在没有见证数据的情况下计算出来的区块哈希。因此,钱包可以在不需要见证数据的同时,获得“工作量证明(PoW)”的保证 。然而,如果想要在节点重新启动时验证所有的见证数据,就必须存储见证数据了。
  4. 区块传播/速率:在最差的情况下,理论上这些的4MB区块具有较差的传播特性。然而,像紧凑区块等技术却减轻了一些这种风险。然而,最近中国市场的震动可能显示出这是一个严重潜在问题。
  5. 宽带:比起1MB的非见证数据区块,4M的区块可能会增加节点/钱包的宽带负担。因此,这是大区块的潜在缺点。虽然也许一些轻型钱包只能下载他们自己交易的见证数据,他们永远不需要下载其他的见证数据,但是他们仍然可以将区块哈希与交易数据相联,从而获得“工作量证明(PoW)”的保证。



BitMEX (www.bitmex.com)

挖矿诱因 – 第一部分 – 难度调整的经济学




挖掘是找到新的比特币区块的随机过程,从而确认用户的交易。这必然是具有竞争性和能源密集型的过程。为了确保网络顺利可靠,每隔两周,挖矿难度会根据期间开采的区块数量而进行调整。 区块之间的平均目标间隔为10分钟。


  • 如果在两个星期的周期内有超过2016个区块被挖掘,挖矿则变得更困难,因此如果哈希值保持不变,预计在接下来的两周内将每10分钟发现一次区块。
  • 如果在两个星期的时间内少于2016个区块被挖掘,挖矿就变得不那么困难了,因此如果哈希值保持不变,预计在接下来的两周内将每10分钟会发现一次区块。
  • 任何一个周期的最大调整是4的基数(即旧有难度的25%至400%的范围)。




  1. 比特币价格上涨
  2. 因为矿工赚取比特币为回报,挖矿利润增加
  3. 进入市场壁垒有限,由于利润率高使得更多的矿工加入
  4. 网络哈希率增加,平均区块间隔下降到10分钟以下
  5. 几个星期后,挖矿难度增加,因此挖矿利润下降
  6. 平均区块间间隔回升到10分钟






下图显示了矿业公司的全球黄金开采总产量。 x轴显示了公司占全球黄金生产的比例,而y轴则是衡量生产一金衡盎司黄金的成本。成本的衡量标准称为“所有可持续成本”(AISC),其中包括生产边际成本(可变成本)和建设矿山所产生的资本投资的年折旧(固定成本)。直线红线代表现货黄金价格。























BitMEX (www.bitmex.com)

ICOs – Part 1 – An Interactive Visualization of the ICO Space

Abstract: In this week’s piece, we look at the world of ICOs.  We present an interactive visualization, that illustrates the entire ICO landscape and the interconnections between people officially affiliated with each ICO.


Interactive ICO team member network map

Source: BitMEX Research, ICO websites, icoHunt own and provided the raw data (Do not use the data without their permission)

Network map notes

  • Blue circles represent ICOs
  • Yellow circles represent ICO team members, advisers or backers
  • Circle size is weighted by number of links to other ICOs
  • Data includes around 500 ICOs &  around 4,900 team members
  • We apologies for any errors, omissions or spelling mistakes

ICO network map viewing tips

  • Modify the number of nodes to around 1,000
  • Alternatively, start with 5 nodes, then gradually press the up arrow to add 10 nodes at a time
  • Displaying all 5,388 nodes may use up significant amounts of system resources
  • An illustration of the type of visualization which can be produced is provided here


The negative implications of the extent of ICO team member interconnections

The above network visualization illustrates the high degree of interconnections between the ICOs, with a few dominant individuals involved in many projects.  Skeptics may therefore argue that it is not feasible for any one individual to be involved in this many ICOs, and this is an indication of misleading marketing, bad practice or inadequate disclosure.


Comparing ICOs & IPOs

Many of the individuals listed in multiple ICOs are often listed as a backer or adviser, rather than as an individual involved in day to day management.  In some ways they may be more of an ICO “sponsor” than someone actively involved in project development.  For example, as the chart below illustrates, the concentration of individuals involved in multiple ICOs compares reasonably well to financial advisers or book-runners involved in IPOs.

Vitalik Buterin is the most prolific person when it comes to ICO involvement.  Our analysis shows he has involvement in at least 13 projects, around 2.5% of the total.  Although if you think of Vitalik’s role as more of a sponsor, then Vitalik has a lower market share than Citibank when it comes to IPOs, which has been the lead bookrunner in 3.7% of the IPOs in the last 12 months.


Market share of advisers (Top 20) – ICO/IPO comparison

Source: BitMEX Research, icoHunt, ICO websites, Bloomberg IPO database
Notes:  The above dataset is from around 520 ICOs and 3,266 IPOs which have occurred in the last 12 months.  The market share is based on the number of offerings, not value of the offerings.


The role of a lead bookrunner in an equity IPO, may be to do the following:

  • Underwrite the offering,
  • Ensure the offering complies with regulations,
  • Ensure price stability and liquidity after the stock lists,
  • Prepare marketing materials for the IPO,
  • Bring management of the company on a tour to see potential investors in a roadshow,
  • Use its investment sales staff to promote the offering to its clients,
  • Assist in the allocation of the shares to the offering participants.

In many ways these responsibilities are similar to the roles of some of the most prominent individuals in our ICO analysis above, certainly with respect to marketing and promotion. However, in the world of ICOs the role of the “sponsor” is a lot more murky.  The individual in question is sometimes said to be the person who originated the idea, is involved in management or even the development of the product.  The ICO market therefore lacks clarity with respect to the roles and responsibilities of the individuals involved.


The initial allocation

The initial allocation of shares during an IPO is often an opaque process.  Typically the bookrunner/adviser decides the allocation on a discretionary basis, with the largest institutional and hedge fund clients favored first, rather than a fair random process or auction driven mechanism.  It is somewhat surprising that financial regulators have not clamped down on this practice. Although a counter argument to regulation is that listing companies should have the freedom to decide who their new shareholders are, if their are multiple bidders.  Unfortunately the bookrunner/adviser seems to have a significant influence on the allocation process.

Despite the opportunity to improve on what IPOs do in this area, the initial allocation process when it comes to ICOs does not appear to be much better.  The initial allocation of ICOs is also a murky process, but in some ways even worse than for IPOs, since earlier or better connected investors sometimes get lower prices. The allocation process can be based on who is friends with the people in the team or other industry connections.  Therefore on balance, despite poor practice, IPOs appear to have a somewhat fairer process when it comes to allocation than ICOs.

Although one could cynically say there is a key difference in the offering process between ICOs and IPOs, this time we are the ones in control.

ICOs – Part 2 – Investment Returns

Abstract: Although the reliability of the data is limited, in this piece we look at the investment returns one would have achieved  by investing in ICOs.  We compare the returns against the amount each ICO raised and look at the historic investment performance of the most prolific ICO advisers.


ICO investor returns (log scale)

Source: BitMEX Research, Coinmarketcap, ICO websites, Reddit comments
Notes: A return of 10x means the investor made 10x their money.  Prices up to 25th September 2017


The integrity of the data

  • In general the quality of pricing data for ICOs is poor, we are likely to have made significant errors in many cases.  We apologies for any inaccuracies.
  • ICOs often have particular circumstances and conditions, for example multiple ICO rounds or offerings in different currencies.  Unfortunately due to a lack of transparency and a high degree of complexity, in some cases, we have not been able to account for all of these particularities in a consistent basis.
  • In some circumstances we may have been unable to determine the ICO price and therefore may have used the price on the first day of trading.
  • There may be some selection bias in our analysis, for example we may be more likely to have investigated the investment performance of ICOs which subsequently turned out to be successful.
  • Unfortunately, in a small number of cases we obtained the ICO price from Reddit comments, due to the lack an alternative source.


ICO investor returns compared to the amount raised in the offering (log scale)

Source: BitMEX Research, Coinmarketcap, ICO websites, Reddit comments, Coindesk
Notes: A return of 10x means the investor made 10x their money


In the above chart we compare the amount raised in the offering with the investment returns of the ICOs.  From looking at the chart, it appears that there is a slight negative correlation, although the correlation is not strong enough to pass rigorous statistical requirements.


ICO investor returns of for the top 20 ICO advisers (log scale)

Source: BitMEX Research, Coinmarketcap, ICO websites, Reddit comments, ICO Hunt
Notes: The numbers in brackets represent the number of ICOs we were able to obtain return data for compared to the total number of ICOs the adviser is involved in


Finally we look at the investment returns of the top 20 most prolific individuals in the ICO space, by number of ICOs.  In many cases, the ICOs occurred very recently and therefore pricing data is not yet available.

The SegWit Transaction Capacity Increase – Part 2 – The First Month After Activation

Abstract: SegWit adoption has grown at a steady pace since activation one month ago and this has surprisingly coincided with a large reduction in transaction fees.  Although we think this drop in fees may be a coincidence, as the absolute level of SegWit adoption in the first month is reasonably low


The first month of SegWit data

As the chart below (figure 1) shows, in orange, SegWit adoption has increased steadily since activation, in a somewhat linear fashion.  Adoption has now reached around 4.5% of transactions.  This should represent a small theoretical c1.6% capacity increase for the network, after just one month.

As figure 1 illustrates, the activation of SegWit does appear to have coincided with a sharp reduction in average transaction fees.


Figure 1 – Transaction fees compared to SegWit adoption

Source: BitMEX Research
Note: Data based on daily averages, up to 20th September 2017


As figure 2 below shows, Bitcoin denominated transaction fees do somewhat correlate with the Bitcoin price and Bitcoin price volatility.  This relationship is probably due to higher Bitcoin prices causing increased levels of transaction demand. The first month since SegWit activation was a period of large Bitcoin price increases and high price volatility, which makes the large transaction fee drop appear somewhat unusual.  The drop is transaction fees appears to start during the period when the price was still rapidly increasing.


Figure 2 – Transaction fees compared to Bitcoin price

Source: BitMEX Research
Note: Data based on daily averages, up to 20th September 2017


As figure 3 below illustrates, SegWit usage is still low compared to non SegWit usage.  Although markets and the price elasticity of demand can be very difficult things to quantify and it is possible that the small 1.6% implied capacity increase caused a reduction in transaction fees, we believe this is unlikely.  Therefore the sharp reduction in transaction fees is likely to be an odd coincidence.

It is therefore too early to tell if SegWit was successful in increasing transaction throughput and lowering transaction fees.


Figure 3 – SegWit adoption compared to old format transactions

Source: BitMEX Research
Note: Data based on daily averages, up to 20th September 2017


An alternative explanation for the fee reduction is that not all of the historic demand was “genuine”.  A spammer could have been attempting to inflate transaction demand and increase transaction fees.  Perhaps the activation of SegWit or launch of Bitcoin Cash meant this spammer now has less reason to continue the expensive attack.  Although there is no direct evidence to support this theory.

挖矿诱因 ─ 第二部分 ─ 为什么中国成为了比特币采矿行业龙头







  • 中国铁矿石进口占世界总量68%
  • 中国铝生产占世界总量54%
  • 中国煤炭消耗占世界总量50%
  • 全球60个在建的核电厂中有22个位于中国。中国在过去10年里核电用量增长占世界增长总量183%(占比超过100%是因为日本在2011年大地震之后将其核反应堆关闭了)
  • 在过去十年,中国水电使用量占世界总量30%,另外中国水电使用量增长占世界增长总量76%




  • 矿场建立高效─普遍认为中国最大的优势之一就是当地的基础设施和专业知识,使得一旦拿到采矿芯片,矿场便可以被迅速的建立起来。据说其他国家在搭建矿场的速度上要比中国慢许多。由于高效的芯片不断的在开发中,能够快速设立矿场是至关重要的。另外,与专业芯片的制造商的地理位置相近也为中国采矿业带来了地缘优势。
  • 发电行业的腐败及合作关系─另一个优势是中国力行的腐败现象。一些比特币矿厂过给主好将采矿设备放置在施内或近的位置。






来源: BP world energy report 2017





来源: Wikipedia












虽然以百分比来说中国的水电基础设施仅占产铝业整体耗电量的10%,但是其规模还是很非常大。中国在2011年至2013年期间为了铝冶炼厂大量投资水电设施,其后 2014年和2015年遇上铝价格走低,如下图所示。由于价格下滑导致生产经济效益降低,许多铝冶炼厂被迫停产,使地方专属水电厂的供电需求也跟着下滑。另外,由于一般水电厂距离市区较远,中国又缺乏特高压(UHV)电力传输基础设施,导致多余的产能无法向大城市输出供电。





来源:The London Metal Exchange




全球各国铝产量(1995年至2016年) – 百万吨铝

来源:BitMEX 研究,US Geological Survey





来源:Rio Tinto


来源: BitMEX 研究,US Geological Survey


铝产能过剩量按地区划分(1995年至2016年) – 百万吨铝

来源: BitMEX 研究, US Geological Survey






水电产能利用率(2004年至2016年) – 百万吨铝当量

来源: BitMEX 研究, US Geological Survey, The International Aluminium Institute




目前中国有几个特高压输电线路项目正在进行中,将从郊区向东部城市提供电力。中国国家电网公司计划在2009年至2020年期间投资880亿美元发展特高压线路。许多线路将在未来几年内完成,这个计划对特币采矿业可能产生非常有趣的影响 。






全球用电量 (TWh)  2016 
比特币采矿*  16.7 0.07%
鋁生产  804.0 3.22%
其他 24,179.0 96.72%
总共 25,000.0 100% 

来源: BitMEX 研究,BP,The International Aluminium Institute, Digiconomist







BitMEX (www.bitmex.com)

1 – World’s top exports
2 – US Geological Survey
3 – BP world energy report 2017
4 – Nuclear Energy Institute
5 – Rio Tinto
6 – The International Aluminium Institute
7 – Bloomberg – China’s Metals Curb Plan
8 – Rio Tinto Annual Report – Page 199
9 – Chalco 2015 Annual Report – Page 11
10 – Reuters – Chinalco plans shutdown of biggest aluminum smelter