That's right - it's the leverage.
Notional value is $100, margin req. $10.
Ok. I'm just trying to understand how the system splits the payment.
jerry has $10 (locked) Elaine paid $10.1. Winner gets $1 ( ($10.1 -$10) x $100 / $10).
system pays jerry $11 and Elaine gets $9. ( where does .1 go)?