  We study the entanglement spectrum of a translationally-invariant lattice
system under a random partition, implemented by choosing each site to be in one
subsystem with probability $p\in[0, 1]$. We apply this random partitioning to a
translationally-invariant (i.e., clean) topological state, and argue on general
grounds that the corresponding entanglement spectrum captures the universal
behavior about its disorder-driven transition to a trivial localized phase.
Specifically, as a function of the partitioning probability $p$, the
entanglement Hamiltonian $H_{A}$ must go through a topological phase transition
driven by the percolation of a random network of edge-states. As an example, we
analytically derive the entanglement Hamiltonian for a one-dimensional
topological superconductor under a random partition, and demonstrate that its
phase diagram includes transitions between Griffiths phases.
