• A hard fork occurs when one cryptocurrency (like bitcoin) breaks off to form a new currency (like bitcoin cash).
  • Hard forks take place when the community wants to make a significant upgrade or disagrees on how to move forward.
  • Examples include bitcoin cash, ethereum classic, and bitcoin gold.

Cryptocurrency Hard Forks: Explained

A hard fork is when one cryptocurrency spins off to create another. Think of it like a train track splitting in two. The new coin (and its blockchain) takes a new direction from the old, but they share the same history. It’s a simple fork in the road.

bitcoin hard fork diagram

Let’s take the example of Bitcoin Cash, which is a hard fork of Bitcoin.

In 2017, the Bitcoin community disagreed on how to make improvements to the network. One group wanted to stay true to the old rules and “protocol.” Another group wanted to make drastic changes to how transactions were processed.

Unable to reach an agreement, the second group “forked” off to create a new blockchain. Bitcoin Cash was born.

Bitcoin Cash shares the same blockchain as Bitcoin right up until the moment it forked. From that point onwards, Bitcoin Cash took its own path with its own rules.

bitcoin cash hard fork
Image credit

Bitcoin has forked countless times as the community seeks to improve the technology or disagrees on how to move forward. These forks are not always successful.

How Hard Forks Work

Every blockchain enterprise has its own rules. Those rules dictate how the system works. How large is each block? What rewards do miners get? How are fees calculated? And so forth. One day, the community disagrees on some tidbit, such as whether new code should be introduced or whether participating miners should receive a bonus.

A successful fork is where most of your users agree, collectively make the changes, and move over to the new blockchain. A contentious or experimental fork is where your users split. Some might stick with the present blockchain, some may migrate to the new blockchain, and some use both. Soon you have two versions of your cryptocurrency with different rules.

A failed fork occurs when too few users leap to the new blockchain. That new cryptocurrency quickly becomes worthless.

Hard forks also happen in the following cases:

  • To fix important security risks found in older versions – It took the dollar more than 300 variations to become today’s counterfeit-resilient currency. Blockchain developers aim to make their blockchains 100% breach-free.
  • To add new functionality – Windows 10 is enormously different from its very first version. Blockchain developers upgrade their versions from year to year, adding functions for improvement.
  • To reverse transactions – If website developers suspected a security breach, they could block the previous fork, declaring all previous transactions non-existent. Their new fork would herald a new start.

Hard Forks Can Mean Free Money

The new blockchain is a replica of the old, so all transactions barreling through blockchain A are replicated on blockchain B. If you’ve joined blockchain B, you receive those coins as well as new ones that are mined on your blockchain. Those new coins are known as an airdrop.

crypto airdrops falling

Image credit

When Bitcoin Cash forked, everyone holding bitcoin received the same number of bitcoin cash tokens, essentially for free.

There is a catch, though. You’ll want a secure, private wallet that supports the airdropped coins on the new fork. If you keep your cryptocurrency on an exchange like Coinbase or Binance, the exchange may keep them.

You’ll also want to check whether the forked coin has a future. The unfortunate truth is that most coins fail. Look at the reputation of the fork developers; what are their reviews? Also, see whether credible blockchain services have inspected and credited the open source code of this new coin.

Are Hard Forks a Good Thing?

Some people in the crypto community oppose forks fearing that the new coin will devalue their old. However, a successful fork usually means good news for traders.

When a new fork is announced, we often see a flurry of traders rushing to buy the coin hoping to get free airdrops. That naturally increases the price.

It’s true that the forked coins often become worthless, but some are successful and ultimately valuable, such as bitcoin cash. You’ll often see a profit from a successful airdrop.

Sometimes the hard fork is widely opposed by the majority of people. When that happens, it can strengthen support for the original coin, sending the price up.

Hard Fork Example: Bitcoin Cash

bitcoin cash logo

In August 2017, a group of Bitcoin stakeholders including investors, entrepreneurs, developers, and China-based miners quarreled over the size of the Bitcoin block. Some wanted to keep the one megabyte (MB) limit coded into Bitcoin by Satoshi Nakamoto himself. Others wanted to increase the size to two MB while other stakeholders fretted it should exceed 9,000!

The team eventually split. Bitcoin loyalists adhered to the old protocol, while critics created a new coin called bitcoin cash.

Bitcoin cash never became as popular as the original bitcoin. In December 2017, bitcoin cash was worth $4,355.62. August, 2018, bitcoin cash sold for $519.12. The research firm Chainanalysis noted that in May 2018, the 17 largest payment processing services processed bitcoin cash payments worth US$3.7 million, down from US$10.5 million two months before

To date, Bitcoin’s hard fork iterations include the following:

  • Bitcoin Platinum (BTP). December 1, 2017. A scam, invented by a South Korean teenager in an attempt to kill the price of bitcoin and profit by betting against it.
  • Super Bitcoin (SBTC). December 15, 2017. Among other changes, Super Bitcoin included smart contract functionality, taking a leaf out of the Ethereum blockchain.
  • Bitcoin God (GOD). December 25 2017. Chandler Guo proclaimed Bitcoin God a Christmas gift to bitcoin holders. Most called it bizarre
  • Bitcoin Uranium (BUM). December 31, 2017. BUM was an attempt to democratize Bitcoin, which critics said had become dominated by a small group of entities over-exerting their power over miners. BUM was created as Satoshi’s original vision. It bummed.
  • Bitcoin Cash Plus (BCP). January 2, 2018. Promised “low fees and reliable confirmations”. It flunked almost from the start.

Bitcoin also spawned Bitcoin Diamond (BCD), Bitcoin Gold (BTG), Bitcoin Atom (BCA), Bitcoin Core (BTX), Bitcoin Private (BTCP or ZCL) and Segwit, among others.

Segwit was a soft fork which is quite a different creature.

What is a Soft Fork?

Hard forks are unique in that the changes are incompatible with the previous protocol. Soft forks are different because the software or protocol changes are compatible with the previous versions.

Think of a hard fork being the difference between PlayStation 3 and PlayStation 4. You can’t play PS3 games on PS4 and you can’t play PS4 games on PS3.

A soft fork, on the other hand, is more like Microsoft Excel. You can use MS Excel 2015, even with MS Excel 2005 running in the background. The upgraded version is compatible with the old. At the same time, the updates in the newer version don’t appear in the old. MS Excel 2015 shows features that don’t appear in MS Excel 2005. The new soft fork has additional – or different – features to its older version.

In other words, soft forks have backward compatibility. The new chain contains the previous rules with additions, while the previous blockchain continues unchanged.

segwit soft fork diagram

Image credit: Reddit user u/k06a

As you can see in the diagram, the SegWit fork of Bitcoin is a “soft fork.” It doesn’t create its own blockchain. It simply upgrades and continues the previous chain. In contrast, the hard forks, like Bitcoin Cash and Bitcoin Gold actively split off.

With a hard fork, you need 90 to 95% of the stakeholders, or nodes, to accept your changes for the system to succeed. For a soft fork, you only need a majority of miners to upgrade and agree on the new version.

Soft Fork Example: The SegWit Solution

One of Bitcoin’s greatest frustrations is its slowness. Ten transactions take about a second to slip through compared to Visa’s 5,000-8,000 transactions per second. This is called the “scalability” problem.

In October 2016, Pieter Wuille, a Bitcoin Core developer, tried to treat this problem by modifying the appearance of the Bitcoin block.

Bitcoin blocks have two sections:

  1. The header with its cryptographic data.
  2. The body with transactions and sender/receiver data.

The bulkier the block, the slower traffic.

Wuille divided transactions from sender and receiver data. He gave each their own blocks, creating, in effect, a freeway where bitcoin transactions zoomed through, while so-called witness boxes (SegWit, short for Segregated Witnesses) with scripts and signatures used the parallel lane.

SegWit is called a “soft fork” since it was compatible with Bitcoin’s old code. All Bitcoin needed was 95% of its miners to accept the changes, which happened in less than a year. The platform didn’t need a separate blockchain and currency to make alterations work.

Update:

Critics complained that Segwit fell short of solving Bitcoin’s congestion problems and that the platform needed major changes to decongest its platform. Dissension led to the string of hard forks like the previously mentioned Bitcoin Cash (BCH). In 2017, Bitcoin developers also promoted hard fork SegWit 2x to magnify blocks from 1 MB to 2 MB. That fork died a week before it was scheduled to occur.

Bottom Line

A hard fork:

  • Results in two new blockchains, both of which share the same past.
  • Changes a fundamental aspect of the blockchain or the rules that govern it.
  • Is not compatible with previous versions.

A soft fork:

  • Does not create a new coin or split the blockchain.
  • Upgrades the system with new features that are compatible with the old version.

It’s as simple as that.

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arm wrestle bitcoin dominance
  • Bitcoin dominance nears 60%, the highest since December 2017.
  • Bitcoin is seen as a “safer” haven during a market decline.
  • Rival coin ethereum is getting flushed by ICOs.

If you’re tracking the cryptocurrency market decline, you’ve probably noticed something strange. Altcoins are falling much harder than bitcoin.

Bitcoin, for example, has fallen 67% from its high last December, but ethereum is currently 84% lower than its all-time high. Ripple XRP is 91% lower.

Bitcoin dominance, meanwhile, has increased rapidly since May, almost touching 60% last week.

As prices decline, traders are moving money out of altcoins into bitcoin. What’s going on here?

What is Bitcoin Dominance?

Bitcoin dominance is the term used to describe bitcoin’s market capitalization compared to other cryptocurrencies.

In early 2017, bitcoin made up 87% of the total cryptocurrency market. It was the most dominant cryptocurrency, by far.

Bitcoin’s dominance was challenged throughout 2017 as altcoins grew in popularity. Ethereum threatened to catch up and even overtake bitcoin. In June 2017, bitcoin’s dominance fell to just 38%. Ethereum was at 31%.

That balance has now shifted back towards bitcoin. It currently stands at 55%.

chart depicting bitcoin, etheruem and ripple market capitalization
Chart: CoinMarketCap

Bitcoin Is the “Safe Haven” of Crypto

Think about the stock market for a moment. Whenever the stock market declines, investors take their money out of risky, speculative stocks and put it in “safer” places. They move money to big, stable companies that aren’t likely to get wiped out. Some move their money into safe assets like gold or the dollar.

The crypto market is the same. When people get spooked, they move their money into something more stable. Bitcoin.

While the average investor might not consider bitcoin “stable,” it is compared to altcoins.

Bitcoin Isn’t Going to Disappear

When the cryptocurrency market declines, there’s a real chance that some altcoins will plunge to zero. Bitcoin, however, is unlikely to disappear.

Track record – Bitcoin has a nine-year history and hasn’t disappeared yet. Investors know that bitcoin has weathered storms before and will probably do so again.

Name-recognition – 71% of Americans have heard of bitcoin. It’s now a small, but important, part of our culture.

Ingrained in the wider economy – Wall Street has opened the doors to bitcoin with the launch of bitcoin futures trading. We will shortly see an exchange-traded fund (ETF) and the entrance of more institutional investors. As bitcoin becomes more ingrained in the wider economy, it’s much less likely to disappear.

Gateway cryptocurrency – If you’re just getting into cryptocurrency, you’re probably going to buy bitcoin. Not just because it’s the largest coin, but because many exchanges require you to purchase bitcoin before buying other cryptocurrencies.

Bitcoin has a stability that other coins don’t. So when the market moves lower, people move their money into something that isn’t going to disappear.

There’s also one more reason why bitcoin dominance is growing:

Ethereum Tokens Are Getting Flushed

Ethereum experienced a wild ride to catch up with bitcoin in 2017. Much of that hype was created by new currencies launching on the Ethereum system.

When new currencies launch on Ethereum, they typically raise money through Initial Coin Offerings (ICOs). Investors use ETH to crowdfund these projects, hence the price of ETH rose.

Now, with millions raised in capital, those ICOs are dumping ETH on the open market, forcing the price down.

So while bitcoin enjoys some stability, ethereum is shedding value fast.

Bitcoin Dominance Pattern

When the cryptocurrency market is stormy, investors flock to bitcoin for some element of safety. In other words, bitcoin dominance is high when prices are low.

However, there’s another interesting correlation. Bitcoin dominance also hit a peak when the currency reached an all-time high in December.

So bitcoin dominance surges at both ends of the spectrum: when prices are low and when they are high.

Why? Well, when prices are high, the mainstream floods into the market. Because of name-recognition, they’re buying bitcoin at a much faster rate than ethereum or ripple.

It seems that altcoins have their moment during the quiet growth periods, while bitcoin dominance occurs at the extreme ends of the market. For now, let’s see if bitcoin will tip past the 60% mark.

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bitcoin ethereum and ripple coins on a black background

The flippening is a hypothetical moment in the future when ethereum, ripple, or another cryptocurrency overtakes bitcoin.

Bitcoin is currently the largest cryptocurrency on the planet, but it’s not impossible to imagine ethereum or ripple catching up.

At the start of 2017, bitcoin had a true monopoly in the world of digital currency. It accounted for 87% of the total crypto market value. By January 2018, that figure had fallen to 33% with ethereum, ripple and others eating into bitcoin’s market share.

Some predict that one of these altcoins (alternative cryptocurrencies to bitcoin) will overtake bitcoin entirely. That future moment is the flippening.

The Rise of Altcoins

While bitcoin dominated the blockchain space for eight years, new cryptocurrency projects were stirring under the surface.

Vitalik Buterin launched Ethereum – a “world computer” which took the concept of blockchain way beyond money transfers. Ethereum became a platform for companies and developers to build anything on the blockchain.

Ripple emerged to revolutionize the way we transfer money between banks and across borders. Ripple’s native cryptocurrency XRP was the fastest growing token in 2017, briefly overtaking ethereum.

These altcoins gained huge media attention through 2017 and rose more than 1,000% in value. The momentum lead many to predict that ethereum and XRP could surpass bitcoin in the coming years.

The Flippening: A Measure of Market Capitalization

It’s worth pointing out that the flippening refers to market capitalization (or market cap), not the price per coin.

For example, XRP is worth just 27c per coin, compared to ethereum’s $195 and bitcoin’s $6,332.

Bitcoin is by far the most expensive coin because there are only 17 million in existence (there are 100 billion XRP tokens and more than 100 million ethers).

Bitcoin, Ethereum and Ripple: Where Do They Stand?

At the time of writing, the top three by market dominance looks like this:

1. Bitcoin – 56%
2. Ethereum -10%
3. Ripple – 6%

chart depicting bitcoin, etheruem and ripple market capitalization
Chart: CoinMarketCap

Through the course of 2018, “the flippening” has moved further away. Bitcoin has re-established its dominance, while altcoins like ethereum and ripple have fallen. This is perhaps because bitcoin is seen as a “safer” haven during the long market downturn.

Could the Flippening Really Happen?

Theoretically, yes. Bitcoin has a number of practical issues that hold it back, not least its transaction speed when compared to other blockchains. There are faster, more efficient projects out there that could, ultimately, become more valuable than bitcoin.

However, bitcoin has one major advantage: reputation. 71% of Americans have heard of it. Could the same be said for XRP?

For most people, bitcoin is the first cryptocurrency they buy. On many of the major exchanges, you have to purchase bitcoin before you can buy an altcoin like ethereum or ripple.

Not only that, but Wall Street is slowly embracing bitcoin. We’ll soon have a bitcoin exchange-traded fund (ETF) and institutional money pouring into the market. That money will go to bitcoin first.

In other words, it’s very difficult to knock bitcoin off the throne, because it’s engrained as the world’s first and largest cryptocurrency.

Ethereum or Ripple?

Let’s say the flippening did happen. Which coin is the most likely to overtake bitcoin?

Ethereum has tremendous practical application. The likes of JP Morgan, MasterCard and Microsoft are all experimenting with the Ethereum system. Others are building dapps, smart contracts and new cryptocurrencies. These projects each require ether as a payment token. As Ethereum grows and develops, the demand for (and the price of) ether may rise higher than bitcoin.

Ripple also has a practical application. Ripple aims to deploy its cryptocurrency, XRP, as a “bridge currency” for banks to transfer money abroad without fees or delays. If the world’s banks opt to use the XRP token, the market cap could soar beyond bitcoin’s. It’s worth pointing out, however, that no bank is yet using XRP beyond a pilot scheme.

Ultimately, Ethereum remains the best candidate if the flipping were to happen, simply because it is easier to buy than ripple. Only a handful of exchanges allow you to purchase ripple with fiat currency (like USD). You can’t buy ripple on Coinbase, for example. Instead, you would have to purchase bitcoin or ethereum before transferring it to another exchange to buy ripple.

The difficulty in buying it means it’s unlikely to overtake bitcoin anytime soon.

Does It Matter?

Ultimately, bitcoin, ethereum and ripple each exist for very different reasons. They are not direct competitors, so comparing them as such doesn’t get us very far.

However, it’s still an important (hypothetical) moment. If another coin overtook bitcoin, it means that particualr coin was being used in a meainstream, day-to-day, practical way. And that’s an exciting prospect for blockchain technology.

There are 17.3 million bitcoins in circulation right now. Only 21 million bitcoins will ever exist which means there are just 3.7 million bitcoins left to be created, or “mined”. However, the question of how many bitcoins are there is much more complicated. Millions have been lost or stolen, making it difficult to pinpoint how many bitcoins are left.

21 million: maximum number of bitcoins that will ever exist

17.3 million: number of bitcoins currently in circulation

3.7 million: number of bitcoins left to be “mined.”

4 Million Bitcoins Are Lost Forever

Theoretically, 17 million bitcoins are out there already, but almost a quarter are gone forever. In the early days of bitcoin, millions were accidentally lost. They were forgotten on hard drives or lost on paper wallets. One man threw away 7,500 bitcoins on an old hard-drive. (People were much less careful about storing cryptocurrencies when they were only worth a few cents each).

infographic depicting the number of bitcoins lost

It’s estimated that up to 3.79 million bitcoins are gone forever (almost a quarter of those currently in circulation). That’s $23.9 billion worth based on today’s price.

5 Million Bitcoins Are Held by a Handful of “Whale” Investors

Then there are the enormous hoards of bitcoin stashed away by early investors. According to Chainalysis, five million bitcoins belong to just 1,600 wealthy people. They’re known as “whales” because they own enough bitcoin to make a splash on the market when they buy or sell.

Among these whales, we know that Bitcoin’s founder, Satoshi Nakamoto is estimated to have nearly 1 million bitcoins in his digital wallet. And the Winklevoss twins own 1% of all bitcoin in circulation.

So if we take into account 4 million “lost” bitcoins and 5 million “whale” bitcoins, that only leaves about 8 million bitcoins left on the open market.

1 Million Bitcoins Are Stolen

But wait, what about stolen bitcoins? 850,000 bitcoins were stolen in the infamous Mt. Gox hack and at least 150,000 were taken in 2016 from the Bitfinex exchange. Many thousands more have been stolen in smaller heists.

While these coins are not lost, they are probably held by thieves and not circulating on the open market.

That leaves around 7 million available bitcoins. To put that into perspective, there aren’t enough freely available bitcoins for each person in New York.

Only 21 Million Bitcoins Will Ever Exist

One of the key features of bitcoin is that only 21 million can ever exist. This number is hard-coded into the system. We are scheduled to hit this hard-cap in the year 2140.

How does it work?

In simple terms, bitcoin is created by a process called “mining.” Without getting too technical, miners are responsible for processing transactions. They are rewarded with bitcoins for doing so.

Miners produce a “block” of transactions every 10 minutes. In return, they get 12.5 bitcoins.

This is how bitcoins enter circulation.

1,800 Bitcoins Are Created Every Day (For Now…)

If a block takes 10 minutes to process and miners get 12.5 BTC per block, that means 1,800 bitcoins enter circulation every day.

However, that number is set to get smaller and smaller over the next century due to a process called “halving.”

Bitcoin Creation Is Halved Every Four Years

When bitcoin was first created, miners were rewarded 50 bitcoins (BTC) for every block,

That reward is halved roughly every four years (after every 210,000 blocks mined).

It was first halved in 2012 (to 25 BTC) and then again in 2016 (to 12.5 BTC).

In other words, the supply of bitcoins will become increasingly limited.

After 64 halvings, we’ll hit the 21 million BTC cap. At this point, no more bitcoins will be created.

bitcoin supply and halving chart
Chart source: bitcoin.it/wiki

81% of Bitcoins Already Exist

Because of the halving system, the vast majority of bitcoins have already been created.

There are only 3.7 million bitcoins left to be mined, but it will take over 100 years to get create them.

What Happens When All Bitcoins Are Mined?

When we hit the 21 million cap, miners will no longer be rewarded directly for processing the blocks. Instead, they’ll be paid a transaction fee for each block they process.

In other words, miners will still receive a payment or incentive to maintain the blockchain.

How Does Bitcoin Supply Compare to Ethereum and Ripple (XRP)?

Coin creation and supply is one thing that separates bitcoin from other cryptocurrencies like ethereum and ripple XRP.

While the bitcoin supply is capped at 21 million, ethereum has no cap. There are already more than 100 million ethereum tokens in circulation. Having said, ether supply is capped at 18 million per year.

Ripple XRP, the third largest cryptocurrency, does have a hard cap of 100 billion, but they already exist. Every XRP token was created at once at inception, so they aren’t mined like bitcoin.

Conclusion: Bitcoin Supply Is Incredibly Limited

Bitcoin is scarce. Only 21 million will ever exist – a considerably smaller number than rival coins. Not only that, but millions are already lost, stolen, or hodled away by early investors.

Couple that with an ever-diminishing supply and there is simply not that much bitcoin left on the open market.

man in a hood on a red background crypto market manipulation

Welcome to the weekend folks! Grab a coffee and let’s recap the biggest news stories of the week in cryptocurrency and blockchain.

It’s been a rough week for bitcoin which plummeted 13% on Wednesday and never really recovered. Ethereum collapsed to its lowest level in over a year and some alt coins racked up 20% losses.

bitcoin price drop
Bitcoin price via CoinMarketCap

What Caused the Selloff?

Some pointed the finger at Goldman Sachs for reportedly shelving its plans for a crypto trading desk.

Others linked the selloff to an old crypto wallet connected to the infamous Silk Road – a dark net platform for selling drugs. A reported 111,000 BTC was moved from the wallet to various exchanges, prompting a huge downturn in price.

Another controversial theory is epic market manipulation. As CCN points out, there was a flurry of bitcoin market activity and trading volume in the moments before the Goldman Sachs announcement. It suggests that insider trading might be at play here.

Thanks to the introduction of futures contracts, a small group of wealthy traders are able to move the markets with relative ease. Because the arena is still relatively unregulated, they can do so without consequence too.

Is that what happened on Wednesday? Perhaps. No matter what the cause, it proves that the crypto market is still heavily influenced by just a handful of whales.

Ethereum Futures Are Coming

purple ethereum logo on blue background

Speaking of bitcoin futures and volatility, we may soon have ethereum futures to add to the storm.

An ethereum futures contract would allow investors to bet on the future price of ether without having to buy the cryptocurrency itself. Theoretically, we should see institutional investors pouring money into the market (much like when bitcoin futures launched).

However, it could also have the opposite effect as ethereum futures contracts would allow traders to bet against the cryptocurrency. Read more here.

Could Blockchain Save Twitter From Scammers?

Congress grilled Twitter and Facebook executives this week over social media’s role in election interference and privacy invasion. One representative from California asked about the potential of blockchain in countering scams. (Something Block Explorer looked into in July).

Twitter’s CEO Jack Dorsey was optimistic about the technology:

“We haven’t gone as deep as we’d like just yet in understanding how we might apply this technology to the problems we’re facing at Twitter, but we do have people within the company thinking about it today.”

Dorsey is already evangelical about bitcoin. He previously said the internet “will have a native currency,” and that he “hopes” it will be bitcoin.

Coinbase is Working on an ETF

Coinbase logo

Who isn’t working on a bitcoin exchange-traded fund (ETF) these days? Despite nine sharp rejections from the Securities and Exchange Commission (SEC) last month, everyone is still scrambling to be the first bitcoin ETF provider.

Coinbase is the latest to join the race. The largest crypto exchange in the US is reportedly in talks with Blackrock to make it happen.

There was more ETF news this week as the SEC appointed a new commissioner, Elad Roisman. Roisman is pro-crypto, leading many to think he may swing the decision in favor of approving the next ETF proposal.

Half of Young Americans Want to Use Crypto

A recent survey revealed that 48% of US millennials are interested in using cryptocurrency as a primary method of payment.

The study also showed that 79% of Americans have heard of bitcoin or some form of cryptocurrency (where have the other 21% been??)

That’s all for this week’s roundup. Enjoy the rest of your weekend, and we’ll see you back here on Monday.

Want More?

Further Reading: Goldman Sachs Shelving its Crypto Trading Desk is a Good Thing. Really.
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