Bitcoin has generated a highly unusual on-chain signal, according to on-chain analyst Willy Woo, who highlighted an unprecedented pattern in nearly 20 years of historical data. Woo pointed to a so-called anomaly in Bitcoin’s HODL Wave metrics, suggesting recent accumulation activity differed dramatically from previous market cycles.
Rare shift in HODL Wave trends
Woo observed that the typical accumulation behavior seen at major Bitcoin bottoms did not emerge this time. Traditionally, the emergence of a new wave of investors creates clear spikes in Bitcoin’s youngest HODL Wave bands, which represent coins held for the shortest time after being purchased.
“We have an ANOMALY,” Woo posted on X, referring to the lack of expected buying spikes. He suggested that the recent bottom was not marked by widespread investor purchases. “Whoever bought the bottom did it slowly. Possibly even a single whale,” Woo wrote, indicating that one or a few large entities may have quietly built significant positions instead of the usual broad-based activity.
Widespread accumulation has historically produced clear spikes in Bitcoin’s youngest HODL Wave bands, with every previous cycle showing obvious bursts in buying—except for the current trend, according to Woo’s analysis.
The HODL Wave model analyzes Bitcoin’s circulating supply by grouping coins according to the length of time since they were last moved. Its youngest bands are considered useful indicators of recent buying as newly held coins initially appear here before aging into higher bands if left untouched.
Normally, a surge of new investors at the bottom would trigger a visible influx into these short-term categories. The absence of such a pattern this cycle led Woo to theorize the involvement of large individual players—or “whales”—steadily accumulating Bitcoin without sparking broader activity.
Woo also noted alternative explanations for the data, acknowledging that factors such as exchange-traded funds (ETFs), institutional custody arrangements, and the growing use of derivatives might contribute to these changing trends in on-chain activity.
Mini dictionary: HODL Wave, an on-chain analysis tool, segments Bitcoin’s total supply into age bands to visualize investor behavior, helping track buying, holding, and spending trends over time.
Market volatility and options expiry
Recent trading sessions have seen Bitcoin fall below the key $77,000 threshold, followed by a subsequent rebound. Despite this recovery, analysts describe the market as fragile, citing uncertainty over potential policy rate increases that may weigh on risk assets.
Adding to volatility, a large batch of cryptocurrency derivatives contracts is set to expire. Coinbase Markets reports that approximately $2.51 billion in Bitcoin and Ethereum options are coming due, with Bitcoin representing the majority of this exposure.
| Asset | Options Expiry Value |
|---|---|
| Bitcoin (BTC) | Majority of $2.51 billion |
| Ethereum (ETH) | Minority of $2.51 billion |
Derivatives expiry events are closely watched by market participants, as they can trigger abrupt price movements depending on prevailing market sentiment and the positioning of large traders.
Changing market dynamics
Woo emphasized that Bitcoin’s overall market structure has evolved considerably in recent years. The increased participation of institutional players, the introduction of spot Bitcoin ETFs, and the proliferation of new custody solutions have all made the landscape more complex.
These shifts mean traditional on-chain signals may require further interpretation, as investor profiles and transaction patterns diversify far beyond early-cycle norms.
While Woo’s anomaly finding stands out against prior HODL Wave data, he cautioned that multiple structural factors—beyond single entities—could be shaping current accumulation patterns in Bitcoin and contributing to its recent volatility.
Major derivatives expiry looms as the cryptocurrency market navigates a delicate phase, with analysts watching for possible turbulence due to macroeconomic policy concerns and large open positions.




