Negative Doubles

Board 6
East Deals
E-W Vul
A 10 6 3 2
10 5 4
Q 10 7
7 3
9 7
A 9 3 2
A 9 5
K 10 9 2
N
WE
S
J
K J 8 6
K J 8 4
Q J 6 4
K Q 8 5 4
Q 7
6 3 2
A 8 5
WestNorthEastSouth
  1112
Dbl344All pass 
  1. E opens 1
  2. S overcalls 1S
  3. Negative double from W showing
  4. Does N Compete with ? Some will....
4 by South