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The recently measured direct CP asymmetries in the processes D 0→ π+ π− and D 0→ K+ K− show a significant deviation from the naive Standard Model expecta-tion. Using a general parameterization of the decay amplitudes, we show that the measured branching ratios imply large SU (3) breaking and large violations of the naive 1/N c counting. Furthermore, rescattering constrains the I= 0 amplitudes in the ππ and KK channels. Combining all this information, we show that, with present errors, the observed asymme-tries are marginally compatible with the Standard Model. Improving the experimental accuracy could lead to an indirect signal of new physics.