5×100=$500 per spread5 \times 100 = \$500 \text{ per spread}5×100=$500 per spread
Your maximum loss is:
$500−$150=$350\$500 - \$150 = \$350$500−$150=$350
The broker requires $500, even though the real risk is just $350, because they don’t subtract the credit from the margin requirement upfront—you just keep the credit as profit if it expires worthless.
这次卖了个put credit spread， 也就是在卖了put的前提下，为了安全起见，同时又买了一个更低价位的put。结果两天以后，Schwab强制卖了我的MM账户上的部分钱。
举例: 卖了$100 strike的put, 收$5 ， 同时买了一个$90 strike的put， 付出$2。 这样万一股票大跌， 我最多损失$7 (=$100-$90+$2-$5)。 Schwab却自动从我MM里卖了$700，变现成了$700 cash。
打电话过去问，为什么我平时光卖put，Schwab不会自动卖我MM上的钱，而卖个更safe的put credit spread却要变卖MM? 对方解释说，这是IRA账户， potentially put spread的两个脚可能同时exercise。 可是我问potentially short put也会exercise，而且risk更高。 对方承认这样的问题，但回答说，系统就是这么规定的。
有更好的解释吗?
而且客服也确认了我setting
你可以改成debit spread就可以了。不过我挺不建议IRA账号用option的。
Margin requirment calculation is not based on the max losses when the options are execised
功能，没有自己是买方又提前exercise的问题。
也就是人家认为二级的下单比一级的要更复杂？
Example:
Sell 1 Put at $100
Buy 1 Put at $95
Net Credit = $1.50
Spread Width = $100 – $95 = $5
Margin requirement:5×100=$500 per spread5 \times 100 = \$500 \text{ per spread}5×100=$500 per spread
Your maximum loss is:
$500−$150=$350\$500 - \$150 = \$350$500−$150=$350
The broker requires $500, even though the real risk is just $350, because they don’t subtract the credit from the margin requirement upfront—you just keep the credit as profit if it expires worthless.