Yes! There is a number of widely known inefficiencies (low vol, mid cap stocks, the trend following anomaly, long volatility oriented strategies...) that consistently produce better risk-adjusted returns. Some of them aren't really popular enough to stand out and reach their full capacity, others (trend following especially) are so counterintuitive that in practice almost no manager nor investor ends up being able to sustain the emotional pressure, eventually everybody cries uncle and there is no way the anomaly gets crowded enough to go away.