  We find systematic signatures suggesting a different superconducting nature
for a triple-layered cuprate Bi$_2$Sr$_2$Ca$_2$Cu$_3$O$_{10+\delta}$ with
respect to a double-layer through the properties of intrinsic Josephson
junctions (IJJs). Our measurements on the current-voltage characteristics
reveal that the $c$-axis maximum Josephson current density is sensitive to the
superfluid density in outer planes while the critical temperature and the
superconducting gap remain unaffected. Switching dynamics of stacked IJJs
exhibit that the fluctuation in gauge-invariant phase difference of an IJJ
implies that the inner plane completely shields the capacitive coupling between
adjacent IJJs, which is essential for mono- and bilayered cuprates.
