Search for $D^0 \to \ell^+\ell^-$ and $D^0 \to \gamma\gamma$ at BaBar and BESIII
Three searches for rare decays of the charmed $D^0$ meson are presented: a search for $D^0 \to \ell^+\ell^-$ published by the BaBar collaboration using about 468 fb$^{-1}$ of data and two searches for $D^0 \to \gamma\gamma$, one published by the BaBar collaboration using about 470 fb$^{-1}$ of data, and a second one presented as a preliminary result by the BESIII collaboration using approximately 2.9 fb$^{-1}$. No statistically significant signal has been found, in agreement with the Standard Model predictions.