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.”
Tan Su Shan, chief executive officer of DBS Group Holdings Ltd., speaking at the Singapore Fintech Festival in Singapore, on Nov. 12, 2025.
Bloomberg | Bloomberg | Getty Images
SINGAPORE – Amid fears of an artificial intelligence bubble, much has been made of recent reports suggesting that AI has yet to generate returns for companies investing billions into adopting the tech.
But that’s not what the chief executive of Southeast Asia’s largest bank is seeing — she says her firm is already reaping the rewards of its AI initiatives, and it’s only just the beginning.
“It’s not hope. It’s now. It’s already happening. And it will get even better,” DBS CEO Tan Su Shan told CNBC on the sidelines of Singapore Fintech Week, when asked about the promise of AI adoption.
DBS has been working to implement artificial intelligence across its bank for over a decade, which helped prepare its internal data analytics for recent waves of generative and agentic AI.
Agentic AI is a type of artificial intelligence that relies on data to proactively make independent decisions, plan and execute tasks autonomously, with minimal human oversight.
Tan expectsAI adoption to bring DBS an overall revenue bump of more than 1 billion Singapore dollars (about $768 million) this year, compared to SG$750 million in 2024. That assessment is based on about 370 AI use cases powered by over 1,500 models throughout its business.
“The proliferation of generative AI has been transformative for us,” Tan said, adding that the company was experiencing a “snowballing effect” of benefits thanks to machine learning.
A major area in which DBS has applied AI is in its financial services to institutional clients, with AI used to collect and leverage data for clients in order to better contextualize and personalize offerings.
According to Tan, this has resulted in “faster and more resilient” teams. The CEO believes that these uses of AI have contributed to a recent uptick in the bank’s deposit growth as compared to competitors’.
The company also recently launched a newly enhanced AI-powered assistant for corporate clients known as “DBS Joy,” which assists clients with unique corporate banking queries around the clock.
ROI concerns
Despite Tan’s strong convictions about AI, recent evidence suggests that many companies are struggling to turn their AI investments into tangible profits.
MIT released a report in July that found 95% of 300 publicly disclosed AI initiatives, encompassing generative AI investments of $30–$40 billion, had failed to achieve real returns.
However, at least in the banking sector, there are signs that the tides are turning.
While DBS doesn’t differentiate spending in generative AI from other in-house investments, other major banks have recently offered this comparison.
JPMorgan Chase CEO Jamie Dimon stated in an interview with Bloomberg TV last month that the bank is already breaking even on its approximately $2 billion of annual investments in AI adoption. That represents “just the tip of the iceberg,” he added.
Those expectations are shared by DBS, which plans to continue to accelerate its AI development to become an AI-powered bank.
The ultimate goal, according to Tan, is for its generative AI to develop into a trusted financial advisor for clients, including retail users who are expected to interact with personalized AI agents through the DBS banking app.
The bank already has over 100 AI algorithms that analyze users’ data to provide them with personalized “nudges,” such as alerts on incoming shortfalls, product recommendations, and other insights.
Continued AI investments
While DBS may already be reaping rewards from its AI adoption, Tan acknowledged that it will require continued investments, not only in capital, but in the time needed to reskill employees.
The company has launched several AI reskilling initiatives across departments this year and has even deployed a generative AI-powered coaching tool to support these efforts.
This will help the company automate mundane work and refocus its staff on building and maintaining human-to-human relationships with customers, rather than reducing headcount, Tan said.
“We’re not freezing hiring, but it does mean reskilling. And that’s a journey. It’s a never-ending journey … a constant evolution.”
The slump in stocks can partly be traced to a turnaround in sentiment regarding artificial intelligence. Tech behemoths such as Nvidia, Broadcom and Oracle slumped, with the last losing more than one-third in value since it rocketed 36% in September.
Investors, it seems, are growing worried over the high valuations of tech names, as well as the gigantic amount of capital expenditure they are committing to — with some, like Oracle, having to take on debt to fulfil those obligations.
Uncertainty over an interest rate cut in December is also putting a downer on Wall Street. It’s a coin toss as to whether the U.S. Federal Reserve will ease monetary policy then, according to the CME FedWatch tool. That’s a huge difference from a month ago, when traders were pricing in a 95.5% chance of a December cut.
Not having October’s employment and inflation numbers, and possibly never getting them, means the Fed lacks visibility into the state of the economy — and whether it should try to support the labor market or continue reining in inflation.
After all, flying blind makes it hard to see where you’ll land. As of now, that applies both to the Fed and investors trying to navigate the still-hazy ambitions of tech companies.
What you need to know today
And finally…
Oracle CEO Clay Magouyrk speaks at a Q&A following a tour of the OpenAI data center in Abilene, Texas, U.S., Sept. 23, 2025.
Two months ago, Oracle’s stock soared 36% to a record after the company blew away investors with its forecast for cloud infrastructure revenue. Since then, the company has lost one-third of its value, more than wiping out those gains.
The mood of late has turned, with investors questioning whether the AI market ran too far, too fast and whether OpenAI can live up to its $300 billion commitment to Oracle over five years. Of the big cloud companies in the GPU business, Oracle is expected to generate the least amount of free cash flow, said Jackson Ader, an analyst at KeyBanc Capital Markets.
Ticket reseller StubHub signage on display at the New York Stock Exchange for the company’s IPO on Sept. 17, 2025.
NYSE
StubHub shares plunged 20% in extended trading on Thursday after the company reported quarterly results for the first time since its initial public offering in September.
Here’s how the ticket vendor did in comparison with LSEG consensus:
Loss per share: $4.27
Revenue: $468.1 million vs. $452 million expected
During a conference call with investors, StubHub CEO and founder Eric Baker said the company wouldn’t provide guidance for the current quarter.
Baker said that the company takes “a long term approach,” adding that the timing of when tickets go on sale can vary, making it hard to predict consumer demand. StubHub plans to offer outlook for 2026 when it reports fourth-quarter results, he said.
“The demand for live events is phenomenal,” Baker said. “We don’t see anything with consumer demand that’s any different.”
Revenue increased 8% in its second quarter from $433.8 million a year earlier, the company said.
StubHub reported a net loss of $1.33 billion, or a loss of $4.27 per share, compared to a net loss of $45.9 million, or a loss of 15 cents per share, during the same period last year. StubHub said this reflects a one-time stock-based compensation charge of $1.4 billion stemming from its IPO.
Gross merchandise sales, which represent the total dollar value paid by ticket buyers, rose 11% year over year to $2.43 billion.
The company faced tough comparisons from a year earlier, when results were boosted by Taylor Swift’s massively popular Eras Tour. Excluding that impact, StubHub said GMS grew 24% year over year.
Founded in 2000, StubHub primarily generates revenue from connecting buyers with ticket resellers. It competes with Vivid Seats, which was taken public via a special purpose acquisition company in 2021; SeatGeek; and Ticketmaster parent Live Nation Entertainment.
“We are building a truly differentiated consumer product that improves the experience for fans while unlocking better economics for venues, teams, and artists through open distribution,” Baker said in a statement. “We’re early in that journey, but our progress so far gives us great confidence in our strategy and the long-term value we’re creating.”
StubHub raised $800 million in its long-awaited IPO on the New York Stock Exchange, which came after it delayed its debut twice. The most recent stall came in April after President Donald Trump‘s announcement of sweeping tariffs roiled markets. The company restarted the process to go public in August when it filed an updated prospectus.
On Thursday, the company’s stock closed at $18.82. Shares are now down roughly 20% from the IPO price of $23.50.
