Bitcoin's (BTC) dominance rate has dropped notably this month, sparking hopes for a full-blown alt season or period where the bull market spreads beyond BTC, lifting valuations in other sectors of the digital assets market. Joao Wedson, CEO and founder of crypto data analysis platform Alphractal, expects a full-blown alt season to unfold in June. Bitcoin's dominance rate, which measures the leading cryptocurrency's share of the total digital assets market, has dropped from roughly 65% to 62% in one week, ending a prolonged five-month uptrend, according to data source TradingView. During the same time, the total crypto market capitalization has increased from $2.90 trillion to $3.24 trillion. The contrast suggests a shift in investor interest from bitcoin toward alternative cryptocurrencies. Per Wedson, the altcoin season is already underway and the BTC dominance is expected to decline rapidly in the coming months. Wedson's proprietary altcoin season index, which focuses on select 57 altcoins, shows 37 of those coins have outperformed BTC in the past 60 days. "Even if BTC drops in the coming weeks, most altcoins have already bottomed out, and it’s unlikely they’ll fall below recent price levels. Part of bitcoin’s $2 trillion market cap is likely to flow into altcoins. So make sure to analyze your altcoin against BTC pairs (e.g., ETH/BTC or COTI/BTC)," Wedson said on a detailed post on X. However, broader measures suggest the bull market has yet to expand beyond BTC. For instance, CoinMarketCap's altcoin index, which focuses on top 100 coins, remains stuck at 27 to suggest "bitcoin season."