Two of the biggest crypto exchanges in the world are run by men who were once colleagues. They shared an office in Beijing, a mission and a company. Since 2015 they have shared only a feud. In April 2026 that feud came back in a way that was striking even for this industry: an offer of one billion dollars, in public, with a 24-hour deadline.
8 April 2026
It started with a book.
Changpeng Zhao — everyone says CZ — published his memoir under the title Freedom of Money. Childhood in Canada, the rise of Binance, the American criminal case, four months in prison. And somewhere halfway through, a few paragraphs about 2014: his short spell at OKCoin, the Chinese bitcoin exchange that would later become OKX.
He wrote that his old boss had accused him back then, “out of nowhere”, of forging a contract.
That old boss is called Star Xu. He runs OKX today. And he was reading along.
Within a day a series of posts appeared on X in which Xu called his former chief technology officer a “habitual liar” — a man who lies as a matter of habit. He added that he had had no intention of coming back to this at all. That he had only been “dragged into it again by that book”.
What followed was about eleven-year-old documents, a notary, a divorce, and in the end about a billion dollars. But the heart of it is simpler than that. These two men are not fighting over a contract. They are fighting over which of them is allowed to be believed.
Two stories about the same departure
To understand why this runs so deep, you have to go back to a moment when the roles were exactly reversed.
In 2014 OKCoin was one of the dominant Chinese bitcoin exchanges. Star Xu was the founder and the boss. Changpeng Zhao was an employee. He came in as chief technology officer — not as a partner, not as a co-founder, but as the man who had to build the trading engine. By his own account with ten per cent of the shares.
He did not last a year. By early 2015 he was gone. And even about that departure there are two completely different stories.
Zhao’s version: he was given insufficient sight of the bank accounts and the finances of the company, began to doubt the way OKCoin was being run, and left when Xu wanted to renegotiate his shareholding.
OKCoin’s version: the problem was Zhao himself. He had allegedly inflated his CV, was fired after less than a year because he could not handle the role, then behaved like a resentful former employee on Reddit and social media, and negotiated in bad faith.
At that moment Zhao was nobody. Xu had the company, the capital, the name. Three years later Zhao would build the biggest exchange in the world and Xu would run the second. Every quarrel since is fought by two men who both still remember exactly what the pecking order once was.
The contract that blew it all up
The open war began over one website: Bitcoin.com.
At the end of 2014 OKCoin struck an agreement with Roger Ver, at the time one of the best-known bitcoin investors in the world and owner of that domain. OKCoin would rebuild the site, improve its findability and put money into it every month. The original deal had a minimum term of five years.
When the relationship broke down, there were suddenly two versions on the table. Zhao says he signed and sent only version seven. OKCoin later came up with a version eight, containing a clause that allowed the agreement to be terminated after six months — while the five-year obligation stayed in place for the other party. Financially very convenient for precisely one of the two.
And here it gets remarkable: both camps accuse each other of the same act. OKCoin said publicly that Zhao had tampered with the contract. Ver said OKCoin had made the forged version, and that “the digital signatures prove it beyond any doubt”. Zhao backed Ver.
On 22 September 2016 Ver filed a lawsuit against OKCoin and claimed $570,000 — ten thousand dollars for every remaining month of the agreement.
Xu brought his own evidence to that: a notarised video in which the QQ account of an OKCoin bookkeeper was opened in front of a notary, with chat logs that in his view tie Zhao to both versions. Zhao’s defence, then and now: his account could have been used by someone else, and digital evidence can be manipulated. In May 2015 he put that denial in public on Reddit.
Someone forged it. Only: who?
There has actually been an investigation. That is the detail missing from almost every piece about this feud.
OKCoin put up a bounty of $20,000 for anyone who could examine the document. Cryptography developer Ben McGinnes took it on and published his findings.
His conclusion came in two parts, and only together do they say anything. Part one: the disputed document is a forgery. Part two: Star Xu was not the one who forged it. In a later explanation McGinnes wrote that the evidence pointed to criminal conduct by a former employee.
That sounds like a verdict. It is not, and we should be honest about that. The bounty came from OKCoin itself; this was not a judge and not an independent regulator. The report names nobody. Anyone who wants to read into it that Zhao did it, can. Anyone who wants to read into it that it was someone else in that office, can too.
And that is exactly why this quarrel is still alive eleven years later: it has actually been established that something was forged, but never by whom.
The keys were with his wife and his mother
After he left, Zhao did not limit himself to the contract. He threw open the whole inner workings of OKCoin, in public, in 2015.
He claimed the exchange used its own bots that placed orders trading only against themselves and not against those of customers — making the trading volume look bigger than it was. He claimed OKCoin had removed a number of those bot accounts to pass the Proof-of-Reserves audit of August 2014. He claimed Star Xu openly encouraged staff to trade on the company’s own platform.
And then the point that sticks most, eleven years on. According to Zhao, Xu was the only one holding the private key of the OKCoin wallet. The backup copies of those keys were, he said, with Xu’s wife and mother, neither of whom was technical.
That is, if it is true, the entire customer holdings of a large bitcoin exchange sitting behind two people who do not know what they are keeping.
OKCoin denied everything. And Zhao himself acknowledged at the time that for part of these operational accusations he had no hard, public evidence. So we write them down as what they are: accusations from one party, never confirmed by a regulator or a judge. Xu turned the attack around: Zhao, he said, wanted to damage the company and was presenting his own role inside OKCoin as far bigger than it had been.
“Star is the only one holding the private key of the OKCoin wallet. The backups were with Star’s wife and mother, neither of them technical.”Changpeng Zhao, May 2015 — an accusation OKCoin denied and that has never been established.
A bet about a divorce
Fast forward eleven years. On 9 April 2026, a day after the opening salvoes, the conversation went in a direction nobody had seen coming.
Xu did not stop at the contract. He brought up Zhao’s marital status: in American court filings his partner was reportedly still described as his wife, while in public Zhao was divorced. The underlying suggestion was not subtle — if you are unclear about that, what does that mean for the question of who really holds the stake in Binance?
Zhao’s answer was not an explanation. It was a bet.
He publicly offered Xu one billion dollars — or any other amount Xu preferred — on the proposition that his divorce had indeed been finalised. Lawyers could inspect the divorce settlement, he added. Publish it he would not.
Xu did not take the bet. His reason: he runs a regulated exchange, and he cannot enter into wagers like that. Instead he put his follow-up question — whether Zhao’s stake in Binance had been legally split in that divorce.
On 10 April the 24-hour window expired. Without acceptance. Without an answer. Millions of views.
And with that the feud had come loose for good from what it was once about. It was no longer about a clause in a contract, but about character, loyalty and the entire life story of two founders.
What is established, and what is not
Stories like this always derail at the same point. So we will spell it out.
Established: Zhao worked at OKCoin in 2014 and left within a year. Two versions of the Bitcoin.com contract exist. OKCoin accused Zhao publicly in 2015; Zhao denied it publicly on Reddit in May 2015. Roger Ver filed a case against OKCoin on 22 September 2016 for $570,000. Ben McGinnes’ investigation concluded that the document is forged and that Star Xu did not do it. In April 2026 the book appeared, Xu called him a habitual liar, and Zhao offered a billion that was not accepted.
Disputed or unproven: who made version eight. What the notarised chat logs actually show. Whether that ten per cent shareholding was renegotiated. And all the operational accusations about bots, Proof-of-Reserves, staff trading and the private keys — none of those have ever been established by a regulator or a judge, and Zhao himself acknowledged that for part of them he had no public evidence.
We take no side here. Not out of caution, but because there is nothing to take a side on. What we do is make clear, sentence by sentence, which camp it comes from.
A small world
The Chinese crypto world of 2015 was small enough that everyone was reading along. The same conferences, the same investors, the same chat groups. A quarrel between a founder and his departed CTO was not a private matter; it was industry news.
In 2017 Zhao founded Binance. Within months more volume was going through it than through most existing exchanges combined. OKCoin grew, via OKEx, into OKX, one of the biggest competitors in spot, derivatives and professional trading products.
And with that the feud changed character. An attack on Zhao no longer hit only his reputation, but Binance. An attack on Xu was automatically about the trustworthiness and the origin story of OKX.
Every old reproach got a commercial edge. On both sides.
Two ways to run an exchange
The two companies sell roughly the same thing. The men behind them ran them in completely different ways, and you see that back in the companies themselves.
Zhao became the face. On X every day, memes, interviews, a personal brand that grew bigger than the company. Binance grew faster than any exchange before or since, and paid for it later.
Xu stayed much further in the background. OKX grew more slowly and went looking for licences sooner — Hong Kong, Singapore, Dubai, and later a MiCA licence in the EU.
But anyone who thinks one has a clean history and the other does not is missing a chapter. In October 2020 OKEx froze all withdrawals for five weeks, while Xu was reportedly the subject of an investigation in China. Customers could not reach their money for weeks.
Two styles, two kinds of problems.
And then they both pleaded guilty
Here comes the twist that appears in almost no piece about this feud.
On 21 November 2023 Binance pleaded guilty to American federal charges and paid $4.3 billion. Zhao stepped down as CEO and served four months.
On 24 February 2025 OKX pleaded guilty to violating American anti-money-laundering law and paid $504.7 million. Prosecutors said more than a trillion dollars in illegal trading had passed through it.
The same accusation. The same country. The same outcome: guilty.
They were right about each other, you could say. Just not on the point they are fighting over.
Binance: $4.3 billion, November 2023. OKX: $504.7 million, February 2025. Both with a guilty plea.The two biggest criminal cases against crypto exchanges in the United States — from the two men who call each other untrustworthy.
“I am not jealous. I am ashamed of him.”
It could have ended in April. It did not.
On 29 June 2026 Zhao sat in Abu Dhabi on The Block’s podcast The Starting Block. Asked about the rivalry, he gave a one-word explanation: jealousy. Xu was jealous of what Binance had become.
Xu answered the next day, on X, asking what exactly there was to envy. Then came the list: the four months in federal prison in 2024. The flash crash of October 2025, over which critics pointed at Binance. And the dismissal of compliance staff who had looked into internal accounts.
His conclusion became the headline across the industry: “I am not jealous of CZ, I am ashamed of him.”
That third point deserves attention, because it is exactly what our own Binance series is about: internal oversight that looked away from accounts it should have investigated. That Xu reaches for it in a quarrel does not make it a proven fact. It does make clear what counts as the most sensitive point in this industry.
“Dont drag me into your fight bro”
In July 2026 Binance announced a formal return to the Philippines. And there it got very small for a moment.
The biggest licensed exchange in that country is Coins.ph. It is run by Wei Zhou — the former chief financial officer of Binance, whom you know from part 3 of our Binance series.
Zhao accused Zhou of having obstructed Binance’s arrival in the Philippines earlier on. Zhou denied it. And Star Xu, always nearby when there is something to say about Binance, amplified Zhou’s earlier criticism of the lack of transparency after the crash of October 2025.
At which point Zhou — who was only trying to run his own exchange — posted the best message of the entire year: “Dont drag me into your fight bro.”
Three former colleagues, three exchanges, one archipelago. The crypto world is still not big.
Two competing origin stories
What this is ultimately about is not a clause from 2014. It is two men who are each defending their own version of history.
In Zhao’s version he was an insider who found an opaque organisation, asked critical questions about accounts and keys, and was then attacked for going public with it.
In Xu’s version Zhao was a disappointing executive who rewrote history after being fired and used his later success to make unproven accusations sound credible.
Business conflicts usually wear off. Not this one — and the reason is simpler than a contract. The moment one suggests that the other was once dishonest, it does not hit the accounts but the story. And in this industry the story is the asset.
On top of that, there is no institution that can close it. No judge has ruled on 2015. No regulator is going to assess a chat log from Beijing. What is left is X, and on X nobody ever wins for good. The billion-dollar bet was the logical end point of that: if there is no referee, you offer money instead. It did not work. It could not have.
What it says about this industry
There is another reason this story sticks, and it is less personal.
Crypto is young enough that the pioneers still know each other personally. They have worked together, lent each other money, shared the same offices, used the same chat groups. In the traditional financial world a conflict like this is settled by lawyers, quietly, with an agreement nobody ever hears about.
Here it happens on a public timeline, with screenshots from 2015 attached.
That is charming as long as it is about who changed which contract. It is less charming when you consider that the same two companies together manage hundreds of billions in customer money, and that both have now pleaded guilty in the same courtroom.
Anyone choosing an exchange does not choose on the basis of who was right in 2015. Choose on licensing, on protection, on what happens when things go wrong. That is in registers. Not on X.
Sources
For the 2015 conflict and the accusations about bots, Proof-of-Reserves and the private keys: CoinDesk, 30 May 2015, which also covers Ben McGinnes’ report. For Roger Ver’s lawsuit: CoinDesk, 22 September 2016. For April 2026: Forbes and CoinDesk; for the 2014–2020 timeline and the contract versions CCN. For the second round of June 2026: The Crypto Times. For the Philippines: BitPinas. For the two criminal cases: the DOJ press release on Binance (21 November 2023) and the one on OKX (24 February 2025). The events of 2014 and 2015 rest on public statements by both parties; there is no court ruling on them. Where this piece reports what one of the two camps claims, that is stated explicitly. Last checked 1 August 2026.