A pattern seen ahead of the 2017 and 2021 bull markets has been observed again in a long-term altcoin market capitalisation chart, drawing attention.
BeInCrypto reported on May 8 that the altcoin season index stood at 35, keeping it in a bitcoin season zone.
X analyst el_crypto_prof pointed to three instances of similar structures over the past decade in a weekly chart of total altcoin market value excluding bitcoin. Total altcoin market capitalisation excluding bitcoin is currently about $1.06 trillion.
The first pattern appeared in 2015 to 2016. After forming an accumulation phase, altcoins rose along an upward trend line, briefly dipped below it at the end of 2016, and then surged in 2017. The second pattern emerged in 2019 to 2020. A compression move near a downward trend line ended with a false breakdown during the March 2020 COVID-19 plunge, followed by an altcoin bull market in 2020 to 2021.
The current move has shown a similar structure since 2023. Altcoins moved along an upward trend line throughout 2024 and recently showed price action near the upper boundary resembling a false break. Benjamin Cowen also mentioned a similar cyclical signal in this cycle.
For this scenario to gain traction, bitcoin dominance needs to turn lower. But bitcoin dominance closed at 60.88 percent on the daily chart, breaking above a 58 to 60 percent range that held from August 2025 to April 2026. The next resistance zone was presented as 66.06 percent, the prior cycle high.
The area around 61 percent has acted as resistance several times. Bitcoin dominance was also pushed back from that level on Oct. 10, 2025 and Nov. 5. But RSI failed to enter a bullish zone and then turned lower, and MACD recently showed a bearish crossover. If bitcoin dominance turns down again, the first support is 59.63 percent and the next is 55.66 percent. If it falls below 59.63 percent, the likelihood of altcoins showing relative strength increases.
The altcoin season index is calculated based on how many of the top 50 cryptocurrencies have outperformed bitcoin over the past 90 days. Stablecoins and asset-backed tokens are excluded. A reading of 75 or higher signals an altcoin season, while 25 or lower signals a bitcoin season.
The current reading of 35 means only about that many of the top 50 altcoins are outperforming bitcoin. At past altcoin season peaks, the index rose above 90. Bitcoin’s share of the total cryptocurrency market capitalisation is also about 60.3 percent as of May 2026.
BeInCrypto reported that the long-term chart’s bullish pattern would need bitcoin dominance to drop below 59.63 percent and the altcoin season index to rise above 50. If bitcoin dominance moves close to 66 percent and the index stays below 50, the pattern could be invalidated, it said.
