SOL leads the divergence in 1W ATM volatility

The reading

What the evidence says

The central distinction is divergent 1W ATM, or at-the-money, implied volatility rather than a common repricing across crypto. BTC 1W ATM IV changed by -1.14 vol points ^[1] to 39.22% ^[2], versus ETH's +0.92 vol points ^[3] to 56.54% ^[4] and SOL's +4.71 vol points ^[5] to 61.73% ^[6] over their matched daily endpoints. SOL's 1W absolute move has a full-captured-history magnitude percentile of 83.3rd percentile ^[7]; this describes its individual move, not the rarity of the cross-asset configuration. The matched 1M comparison supports the directional split: BTC changed by -0.36 vol points ^[8] to 38.11% ^[9], ETH by +0.78 vol points ^[10] to 54.33% ^[11], and SOL by +1.08 vol points ^[12] to 57.18% ^[13]. SOL's larger 1W increase therefore has a broader 1M counterpart, while its 3M change of -0.18 vol points ^[14] limits any claim of uniformly firmer SOL ATM volatility.

Directional asymmetry moved differently from ATM volatility. RR25 measures call-versus-put IV asymmetry: BTC 1W RR25 changed by +1.72 vol points ^[15] to -2.72 vol points ^[16], ETH by +2.29 vol points ^[17] to -4.12 vol points ^[18], and SOL by +0.52 vol points ^[19] to -2.87 vol points ^[20]. Existing downside biases eased but remained negative, including where 1W ATM IV rose. Matched 1M RR25 changes of +0.73 vol points ^[21] for BTC, +0.45 vol points ^[22] for ETH and +0.05 vol points ^[23] for SOL show that skew relief extended beyond 1W, though SOL's 1M adjustment was slight. BF25, the average wing IV premium over ATM, also needs tenor-specific interpretation. Its 1W changes were -0.24 vol points ^[24] for BTC, -0.19 vol points ^[25] for ETH and -0.07 vol points ^[26] for SOL. At 2W, BTC BF25 changed by -0.17 vol points ^[27] to 0.97 vol points ^[28], ETH by -0.13 vol points ^[29] to 1.78 vol points ^[30], and SOL by +0.01 vol points ^[31] to 1.60 vol points ^[32]. Matched 1M BF25 changes were -0.03 vol points ^[33], -0.01 vol points ^[34] and +0.12 vol points ^[35], respectively. Thus the shared 1W butterfly-premium narrowing does not describe every tenor, nor does it establish falling absolute wing IV.

Spot performance further separates the ATM and skew readings. Over the crypto daily comparison, BTC spot changed by -1.12% ^[36], ETH by -4.47% ^[37] and SOL by -2.90% ^[38]. ETH's weaker spot performance therefore coexisted with a smaller 1W ATM increase than SOL's, weakening a simple ordering of volatility repricing by spot losses. Across the common trailing realized-volatility window, BTC measured 43.16% ^[39], ETH 55.39% ^[40] and SOL 62.98% ^[41]. Forward 1W ATM IV minus trailing realized volatility was -3.94 vol points ^[42] for BTC, +1.15 vol points ^[43] for ETH and -1.25 vol points ^[44] for SOL. SOL's rising 1W ATM IV still sat below its trailing realized measure, while ETH's sat above its own. These describe different forward and backward windows; they do not identify cheap options or a trading edge.

BTC's easing 1W and 1M ATM IV should also be distinguished from broader BTC volatility benchmarks. The fitted-surface DS30 measure was 43.11 vol points ^[45], while the independently timed BVIV reference was 41.99 vol points ^[46]; BVIV minus DS30 was -1.12 vol points ^[47]. Their different construction prevents treating either as interchangeable with fitted 1M ATM IV. Meanwhile, Wu Blockchain flagged prospective US inflation releases as potential rate catalysts. That shared event backdrop makes the divergent BTC, ETH and SOL 1W ATM responses worth monitoring, but supplies no explanation for their relative magnitudes. The relevant distinction remains firmer altcoin 1W ATM volatility alongside easing 1W downside asymmetry, with supportive but smaller altcoin 1M ATM increases.