  CP violation (CPV) in $D^0-\overline{D^0}$ mixing is described in terms of
the dispersive and absorptive `weak phases' $\phi_f^M$ and $\phi_f^\Gamma$.
They parametrize CPV originating from the interference of $D^0$ decays with and
without dispersive mixing, and with and without absorptive mixing,
respectively, for CP conjugate hadronic final states $f$, $\bar f$. These are
distinct and separately measurable effects. For CP eigenstate final states,
indirect CPV only depends on $\phi_f^M$ (dispersive CPV), whereas
$\phi_f^\Gamma$ (absorptive CPV) can only be probed with non-CP eigenstate
final states. Measurements of the final state dependent phases $\phi_f^M$,
$\phi_f^\Gamma$ determine the intrinsic dispersive and absorptive mixing phases
$\phi_2^M$ and $\phi_2^\Gamma$. The latter are the arguments of the dispersive
and absorptive mixing amplitudes $M_{12}$ and $\Gamma_{12}$, relative to their
dominant ($\Delta U=2$) $U$-spin components. The intrinsic phases are
experimentally accessible due to approximate universality: in the SM, and in
extensions with negligible new CPV phases in Cabibbo favored/doubly Cabibbo
suppressed (CF/DCS) decays, the deviation of $\phi_f^{M,\Gamma}$ from
$\phi_2^{M,\Gamma}$ is negligible in CF/DCS decays $D^0 \to K^\pm X$, and below
$10\% $ in CF/DCS decays $D^0 \to K_{S,L} X$ (up to precisely known
$O(\epsilon_K)$ corrections). In Singly Cabibbo Suppressed (SCS) decays, QCD
pollution enters at $O(\epsilon)$ in $U$-spin breaking and can be significant,
but is $O(\epsilon^2)$ in the average over $f=K^+K^-$, $\pi^+\pi^-$. SM
estimates yield $\phi_2^M, \phi_2^\Gamma = O(0.2\%)$. A fit to current data
allows $O(10)$ larger phases at $2\sigma$, from new physics. A fit based on
naively extrapolated experimental precision suggests that sensitivity to
$\phi_2^{M}$ and $\phi_2^{\Gamma}$ in the SM may be achieved at the LHCb Phase
II upgrade.
