  It is known that the existing experimental limit for$ CPT $ violation is
rather poor; the 10 \% level at best. The $ \DSDQ $ rule is tested only up to 2
\%. In this note, we discuss the possibility of measuring $ T, CP, CPT $ and $
\DSDQ $ rule violations in the neutral $ K $ meson system. It is shown that not
all the symmetry breaking parameters can be determined at a symmetric $ \phi $
factory. Experiments with $ K^0 $ and $ \bar{K}^0 $ beams are needed to test
all the symmetries.
