first word       second word
 +---------------+---------------+
 |  $XUNIT flag  |       o-------+----+
 +---------------+---------------+    |
                                      |
 entry in $OWNER monitor table        |
                                      |
                                      |
                                      |
          +---+---+---+---+           |
          | 3 | 2 | 1 | 0 |<----------+
          +---+---+---+---+
          |       .       |
          ~       .       ~
          |       .       |
          +---+---+---+---+
          | 77| 76| 75| 74|
          +---+---+---+---+

  extended-ownership handler table 
  containing 64(decimal) ownership nibbles