下面是options limit (等价股票数量，options还要除100）：
Equity & Index Option Position Limits
Overview:
Equity option exchanges define position limits for designated equity options
classes. These limits define position quantity limitations in terms of the
equivalent number of underlying shares (described below) which cannot be
exceeded at any time on either the bullish or bearish side of the market.
Account positions in excess of defined position limits may be subject to
trade restriction or liquidation at any time without prior notification.
Background:
Position limits are defined on regulatory websites and may change
periodically. Some contracts also have near-term limit requirements (near-
term position limits are applied to the side of the market for those
contracts that are in the closest expiring month issued). Traders are
responsible for monitoring their positions as well as the defined limit
quantities to ensure compliance. The following information defines how
position limits are calculated;
Option position limits are determined as follows:
Bullish market direction -- long call & short put positions are aggregated
and quantified in terms of equivalent shares of stock.
Bearish market direction -- long put & short call positions are aggregated
and quantified in terms of equivalent shares of stock.
The following examples, using the 25,000 option contract limit, illustrate
the operation of position limits:
Customer A, who is long 25,000 XYZ calls, may at the same time be short 25,
000 XYZ calls, since long and short positions in the same class of options (
i.e., in calls only or in puts only) are on opposite sides of the market and
are not aggregated
Customer B, who is long 25,000 XYZ calls, may at the same time be long 25,
000 XYZ puts. Rule 4.11 does not require the aggregation of long call and
long put (or short call and short put) positions, since they are on opposite
sides of the market.
Customer C, who is long 20,000 XYZ calls, may not at the same time be short
more than 5,000 XYZ puts, since the 25,000 contract limit applies to the
aggregate position of long calls and short puts in options covering the same
underlying security. Similarly, if Customer C is also short 20,000 XYZ
calls, he may not at the same time have a long position of more than 5,000
XYZ puts, since the 25,000 contract limit applies separately to the
aggregation of short call and long put positions in options covering the
same underlying security.
