Rule 6-4-5 Is return as last statement of a switch-clause also compliant to this rule?

[ProgCPlusPlus]

Rule 6-4-5 requires an unconditional throw or break statement to terminate every non‑empty switch-clause.

But what about a return statement like in the example below.

Code:

switch ( x )
{
case 0:
   return;   // Compliant or non-compliant?
case 1:      // Compliant - empty drop through
   case 2:   // allows a group
   break;    // Compliant
case 3:
   throw;    // Compliant
case 4:
   a = b;
             // Non-compliant - non empty drop through
default:
   ;         // Non-compliant – default must also have "break"
}

The return statement for case 0: avoids an unintentional fall-through to next switch-clause.

For that reason an unconditional return at end of a switch-clause should make the switch-clause also compliant to this rule.

Is return as last statement of a switch-clause also compliant to this rule?