The puck must at all times be kept in motion. Play shall not be
stopped because the puck is frozen along the boards by two or more opposing
players, unless a player falls on or is knocked down onto the puck. If one
player freezes the puck along the boards or if a player deliberately falls on
the puck a minor penalty for delaying the game shall be assessed under
Rule 609(e) or Rule 612(a).
Notwithstanding the above, the Referee may stop play along the boards if in
his judgment allowing play to continue will lead to unnecessary contact
surrounding the puck.