  In this work we analyze the observable asymmetries one can build from
entangled B-meson states, in order to extract information on the parameters
epsilon and delta which govern indirect violation of discrete symmetries. The
traditionally proposed observables, based on flavour tags, are not helpful for
the study of the Bd-system, where the tiny value of the width difference
between physical states clears up such asymmetry effects. Our study makes
instead use of CP tags in order to build new asymmetries where the different
parameters can be separated out. For this separation, it is decisive to achieve
a good time resolution in the measurement of entangled state decays.
Nevertheless, even with no temporal information, as would be the case in a
symmetric factory, it is still possible to extract some information on the
symmetries of the system. We discuss both genuine and non-genuine observables,
depending on whether absorptive parts can mimic or not asymmetry effects.
