September was a rough month for crypto investors, in particular for those betting big on ether, the token tied to the ethereum blockchain.
Etherdropped 13% for the month, its second-biggest monthly decline in the past year, behind only a 16% slide in June. Bitcoin fell 7% in September.
It’s difficult to link short-term price movements to any specific event, and with the historic rally in crypto over the past 12 months, pullbacks are to be expected. Ethereum, the second most-valuable cryptocurrency behind bitcoin, is still up about 830% in the past year.
Investors are now buying the September dip. On Friday, the first day of October, ether and bitcoin both climbed over 9%.
Ether 12-month price chart
CNBC
But the September roller-coaster reflects a particularly rocky stretch for the ethereum ecosystem, which has given investors and developers reasons for concern.
The speed of the network and high transaction fees continue to be a problem. The “London” upgrade in August was supposed to make transaction fees less volatile, but it’s had a limited effect.
Meanwhile, rival blockchains dubbed “ethereum killers” are taking advantage of ethereum’s challenges.
Ethereum also unexpectedly split into two separate chains in late August, after someone exploited a bug in the software that most people use to connect to the blockchain. That exposed the network to an attack, and not for the first time.
“All these factors could be having some impact on the speculation side, no doubt,” said Mati Greenspan, founder and CEO of Quantum Economics, in an interview. “But don’t forget that ethereum has appreciated quite handsomely so far this year and the entire market seems to be in consolidation at this time. So I wouldn’t try to read too deeply into these short-term movements.”
Still, ethereum, which serves as the primary building block for all sorts of crypto projects, like non-fungible tokens (NFTs), smart contracts and decentralized finance (DeFi), has some major hurdles to overcome to fend off the emerging competition.
Ethereum’s unexpected split
A central premise of ethereum’s security stems from the existence of only one set of virtual books, meaning you can’t create coins out of thin air. That ledger has to work, because the decentralized nature of the blockchain means there’s no rule keeper or bank that sits in the middle of transactions to act as accountant.
Ethereum developers were rightly alarmed in August when the chain split because of a bug.
“This fork temporarily created two separate records of transactions on the ethereum network – like parallel books,” said Matt Hougan, chief investment officer at Bitwise Asset Management, which created the first cryptocurrency index fund.
For a while, it was unclear whether the split would lead to a “double-spend attack,” where the same token can be spent more than once and transactions can be reversed, Hougan said.Smart contracts overseeing billions of dollars in assets could have also been at risk. Smart contracts allow people to build applications on top of ethereum with self-executing code, eliminating the need of third parties to handle transactions.
Such an attack would have been difficult to execute, since it was clear which nodes were on the correct side of the split and which were not. “But in theory, there was a risk,” Hougan said.
The good news for miners and exchanges is that most of them upgraded their software as recommended and the issue was resolved relatively quickly, said Tim Beiko, the coordinator for ethereum’s protocol developers.
Auston Bunsen, co-founder of QuikNode, which provides blockchain infrastructure to developers and companies, said it was a “responsibly disclosed vulnerability.”
“This is a reminder that blockchains in general and ethereum specifically are new and disruptive technologies,” Hougan said. “They can do amazing things – settle $1 billion transactions in minutes and program money like software – but they are not fully mature.”
Bugs keep happening
The longer-term problem for ethereum is that random glitches like this keep happening.
In April, the ethereum blockchain was hit with a bug in one of the software programs used to access it. And in November, many of ethereum’s DeFi apps temporarily went down after a Geth upgrade debacle, which led to the chain splitting in two.
Geth is short for for Go Ethereum. To access the ethereum blockchain, operators and miners have their pick of software. Most use Geth, which accounts for 64% of the network.
When the ethereum blockchain broke in half a few weeks ago, it was becauseGeth had a bug in its consensus mechanism. That’s what creates the single source of truth for transactions so everyone sees the same thing regardless of what software they’re using.
Developers discovered the bug, put out a new release with a fix and publicly told everyone to update. A lot of users upgraded, but others didn’t. When an unknown actor exploited the bug, ethereum forked, meaning that it broke into two separate chains: one for those who had updated their software and one for those who had not.
Ethereum “sought the veneer of decentralization by having many clients, but as a consequence, they have incompatibilities,” said Nic Carter, co-founder of blockchain data aggregator Coinmetrics.
When the software programs don’t talk to one another, it creates problems for the network.
Bitcoin takes a very different approach. It relies on a highly secure software program for nodes to access the blockchain. Bitcoin developers have long sought to avoid hard forks at all costs, so all changes in the core software tend to be opt in rather than pushed out to users,according to Carter.
“Ethereum prioritizes faster development, but that comes at the cost of a more fragile set of software implementations,” Carter said.
Some crypto experts attribute ethereum’s success to its first-mover advantage. Most NFTs and 78% of DeFi apps, or dApps, run on ethereum, according to the website State of The Dapps.
That’s starting to change, thanks to the growing popularity of rival blockchains.
Even before this latest split in the blockchain, users were complaining about ethereum’s heavy congestion and high transaction fees, which touched a record of $70 earlier this year, and just this week, bounced from $20 to $46 and back down to $32.
‘Ethereum killers’
At current prices, fees continue to drive some users away.
They’re turning to blockchains like Cardano, a platform used to build dApps, and Solana, whose native coin has risen nearly 4,800% since September 2020. Launched last year, Solana is gaining traction in the NFT and DeFi ecosystems because it’s cheaper and faster to use than ethereum.
Investors who had been largely focused on ethereum “have been increasingly diversifying their holdings to other cryptocurrencies, fueling alternative blockchains like Algorand, Solana and Cardano,” said Mark Peikin, CEO of Bespoke Growth Partners.
Bunsen tells CNBC that while Solana is making good strides in terms of being a usable blockchain, it’s not yet decentralized enough to satisfy the larger crypto community.
It’s also not immune to bugs. Last month, Solana suffered a 17-hour outage following a denial-of-service attack, which took the form of a flood of transactions caused by bots.
The list of so-called ethereum killers is long, and includes blockchains like Matic and Polygon, which are complementary to ethereum, according to Bunsen, as well Cardano, which is known for its security.
“I think some of those ethereum killers will make it,” said Bunsen. “But they won’t kill ethereum.”
Ethereum also has its own upgrade in the works. For several years, it’s been building ethereum 2.0, which is expected to be ready by the first quarter of 2022.
The makeover will move ethereum to a less energy-intensive mining process and, according to network founder Vitalik Buterin, could boost speed by over 7,000-fold to 100,000 transactions per second.
If it’s successful, Bunsen said, ethereum 2.0 will be a “huge upgrade in terms of throughput to the ethereum network and a huge win for the environment generally.”
Tyler Winklevoss and Cameron Winklevoss (L-R), creators of crypto exchange Gemini Trust Co., on stage at the Bitcoin 2021 Convention, a cryptocurrency conference held at the Mana Convention Center in Wynwood in Miami, Florida, on June 4, 2021.
Joe Raedle | Getty Images
Gemini Space Station, the crypto company founded by Cameron and Tyler Winklevoss, priced its initial public offering at $28 per share late Thursday, according to Bloomberg.
A person familiar with the offering told the news service that the company priced the offering above its expected range of $24 to $26, which would value the company at $3.3 billion.
Since Gemini capped the value of the offering at $425 million, 15.2 million shares were sold, according to the report. That was a measure of high demand for the crypto company, which had initially marketed 16.67 million shares. Earlier this week, it increased its proposed price range from between $17 and $19 apiece.
A Gemini spokesperson could not confirm the report.
The company and the selling stockholders granted its underwriters — led by and Goldman Sachs, Citigroup and Morgan Stanley — a 30-day option to sell an additional 452,807 and 380,526 shares, respectively, per the registration form. Gemini stock will trade on the Nasdaq under ticker symbol “GEMI.”
Up to 30% of the shares offered will be reserved for retail investors through Robinhood, SoFi, Hong Kong-based Futu Securities, Singapore’s Moomoo Financial, Webull and other platforms.
Gemini, which primarily operates as a cryptocurrency exchange, was founded by the Winklevoss brothers in 2014 and holds more than $21 billion of assets on its platform as of the end of July.
Initial trading will give the market a sense of how long it can keep the crypto IPO party going. Circle Internet and Bullish had successful listings, but there has been a recent consolidation in the prices of blue chip cryptocurrencies like bitcoin and ether. Also, in contrast to those companies’ profitability, Gemini has reported widening losses, especially in 2025. Per its registration with the Securities and Exchange Commission, Gemini posted a net loss of $159 million in 2024, and in the first half of this year, it lost $283 million.
This week, however, Gemini received a big vote of institutional confidence when Nasdaq said it’s making a strategic investment of $50 million in the crypto company. Nasdaq is seeking to offer its clients access to Gemini’s custodial services, and gain a distribution partner for its trade management system known as Calypso.
Gemini also offers a crypto-backed credit card, and last month, launched another card in partnership with Ripple. The latter garnered more than 30,000 credit card sign-ups in August, a new monthly high that was more than twice the number of credit card sign-ups in the prior month, according to the S-1 filing.
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Microsoft Chairman and Chief Executive Officer Satya Nadella (L), speaks with OpenAI Chief Executive Officer Sam Altman, who joined by video during the Microsoft Build 2025, conference in Seattle, Washington on May 19, 2025.
Jason Redmond | AFP | Getty Images
OpenAI on Thursday said its nonprofit parent will continue to have oversight over the company and will own an equity stake of more than $100 billion.
The artificial intelligence startup, recently valued at $500 billion, said this structure will make the nonprofit “one of the most well-resourced philanthropic organizations in the world,” and will allow the company to continue to raise capital.
OpenAI also announced it has signed a non-binding memorandum of understanding with Microsoft, which outlines the next phase of their partnership. Microsoft has invested over $13 billion in OpenAI, backing the company as early as 2019, three years before the launch of of the chatbot ChatGPT.
“We are actively working to finalize contractual terms in a definitive agreement,” OpenAI said in a joint statement with Microsoft, which is also the company’s key cloud partner. “Together, we remain focused on delivering the best AI tools for everyone, grounded in our shared commitment to safety.”
In May, OpenAI bowed to pressure from civic leaders and ex-employees, announcing that its nonprofit would retain control even as the company was restructuring into a public benefit corporation. OpenAI was founded as a nonprofit research lab in 2015, but has in recent years become one of the fastest-growing commercial entities on the planet.
OpenAI said Thursday it is working closely with the California and Delaware Attorneys General to establish its structure.
“OpenAI started as a nonprofit, remains one today, and will continue to be one – with the nonprofit holding the authority that guides our future,” the company’s Chairman Bret Taylor said in a statement Thursday.
The startup has been engulfed in a heated legal battle with Elon Musk, one of its co-founders. Musk has been trying to keep OpenAI from converting into a for-profit company as he competes in the generative AI market with his own startup, xAI.
OpenAI said its nonprofit is also opening applications for the first phase of a $50 million grant initiative that is aimed to support other nonprofit and community organizations across AI literacy, economic opportunity and community innovation.
Microsoft CEO Satya Nadella departs following a meeting of the White House Task Force on AI Education in the East Room of the White House in Washington on Sept. 4, 2025.
Eric Lee | Bloomberg | Getty Images
Microsoft CEO Satya Nadella told employees in a meeting on Thursday that the company has work to do to smooth relations with employees after announcing several rounds of layoffs and a mandated partial return toin-person work.
In the meeting that was held online, an employee asked executives to speak about a perceived lack of empathy in the company’s culture as of late and steps Microsoft is taking to rebuild trust with its workforce.
“I deeply appreciate that, the question and the sentiment behind it,” Nadella said, in audio that was obtained by CNBC. “I take it as feedback for me and everyone in the leadership team, because at the end of the day, I think we can do better, and we will do better.”
Nadella’s comments come after Microsoft slashed 9,000 jobs in July, following smaller reductions in the months prior. On Tuesday, Microsoft said workers living near its headquarters in Redmond, Washington, must come into the office three days a week, starting in February, with a broader rollout to follow.
Amy Coleman, Microsoft’s human resources chief, said at Thursday’s meeting that reception to the return-to-office announcement has been mixed, with some workers feeling like they’re losing autonomy. But she said that employees in and around Seattle already come in, on average, 2.4 times each week.
Like most of the tech industry, Microsoft went fully remote during the pandemic, and made particular use of its internal Teams video and chat offerings, which gained rapid adoption during that period. Microsoft has been slower than many of its peers to put a mandate in place for coming back to the office. Amazon, one of Microsoft’s top rivals, called employees back to offices five days a week in January.
While Nadella and the executive team are taking criticism from some staffers, Wall Street is applauding the company’s growth and execution. The stock is up almost 20% this year, outperforming the broader market, pushing Microsoft’s market cap to $3.7 trillion, which trails only Nvidia among the world’s most-valuable companies.
In July, Microsoft reported a 24% increase in net income to $27 billion. The company’s gross margin was under 69%, compared with 71% in late 2023. It’s rapidly building and renting data center infrastructure to meet artificial intelligence demand.
Nadella said at the meeting that with remote work, new employees and those who are early in their careers don’t always feel a sense of apprenticeship or mentorship.
“Management is just mostly all remote, but the interns are all, you know, in one location,” he said. “And so those are things that just will break a social contract.”
Microsoft didn’t immediately provide a comment.
Even with Microsoft’s rapid expansion, Nadella said the company is feeling the pressure. It’s a common theme in the software industry, as concerns proliferate about the impact of AI and its potential to automate work.
“We have some very, very hard work ahead of us, and that hard process of renewal is essentially what we have to do,” Nadella said. “You have to be hardcore in terms of an intellectual honesty about what really needs to happen.”
Microsoft’s Azure cloud business grew 39% in the latest quarter, but revenue in the Windows and devices business increased by just 2.5%.
“Some of the biggest businesses we built may not be as relevant going forward,” Nadella said. “Some of the margin that we love today may not be there tomorrow, and that means you have to be way ahead of all of those going away, right?”
Microsoft, which celebrated its 50th anniversary in April, will retain its core values as it confronts market realities, Nadella said.
“Capital markets have one simple truth,” he said. “There is no permission for any company to exist forever.”
That wasn’t the only contentious topic at the meeting.
Employees are awaiting details from a third-party investigation after The Guardian said in August that Israel’s military used Microsoft’s Azure cloud infrastructure to store Palestinians’ phone calls as part of Israel’s invasion of Gaza. Microsoft has fired five employees following protests at its headquarters in Redmond, according to a statement from the group No Azure for Apartheid.
Microsoft President Brad Smith, whose office the protesters entered, addressed the issue on Thursday. He said that he and Coleman met with Jewish Microsoft employees, who have been harassed and threatened and have seen their public information shared online.
“We don’t get to control what happens outside Microsoft, but we need to be clear about one thing,” Smith said. “There is no room for antisemitism at Microsoft, and as a company and as a community, we will protect this group and defend them from that.”