Market beta treats all market movements alike: it measures how much an asset covaries with the market, regardless of what moved the market. But if some market fluctuations are unrelated to fundamentals relevant for marginal utility, this covariance need not represent compensated risk. I formalize this idea by decomposing market beta into exposure to SDF-relevant (“priced”) and SDF-orthogonal (“unpriced”) market fluctuations. Under a priced-market spanning restriction, only priced beta predicts expected returns, while unpriced beta has a zero structural price. Conventional CAPM pricing errors therefore arise when assets load differently on the two components. Empirically, these exposures differ substantially across stocks. Priced beta predicts average returns, unpriced beta carries little independent premium, and CAPM pricing errors increase with the gap between them. The CAPM’s performance therefore depends not simply on how much the market moves, but on what moves it.