Option Strategies
Bear Put Ladder
Introduction
Bear put ladder, also known as long put ladder, is a combination of a bear put spread and short put with a lower strike price than the 2 legs of the put spread. All puts have the same underlying Equity and expiration date. This strategy profits from low volatility of the underlying asset. For instance, the underlying price stays similar to its current price.
Implementation
Follow these steps to implement the bear put ladder strategy:
- In the
initialize
method, set the start date, end date, cash, and Option universe. - In the
on_data
method, select the expiration and strikes of the contracts in the strategy legs. - In the
on_data
method, select the contracts and place the orders.
def initialize(self) -> None: self.set_start_date(2017, 4, 1) self.set_end_date(2017, 4, 22) self.set_cash(1000000) self.universe_settings.asynchronous = True option = self.add_option("GOOG", Resolution.MINUTE) self._symbol = option.symbol option.set_filter(lambda universe: universe.include_weeklys().put_ladder(30, 5, 0, -5))
def on_data(self, slice: Slice) -> None: if self.portfolio.invested: return # Get the OptionChain chain = slice.option_chains.get(self._symbol, None) if not chain: return # Select the put Option contracts with the furthest expiry expiry = max([x.expiry for x in chain]) puts = [i for i in chain if i.expiry == expiry and i.right == OptionRight.PUT] if not puts: return # Select the strike prices from the remaining contracts strikes = sorted(set(x.strike for x in puts)) if len(strikes) < 3: return low_strike = strikes[0] middle_strike = strikes[1] high_strike = strikes[2]
Approach A: Put the OptionStrategies.bear_put_ladder
method with the details of each leg and then pass the result to the buy
method.
option_strategy = OptionStrategies.bear_put_ladder(self._symbol, high_strike, middle_strike, low_strike, expiry) self.buy(option_strategy, 1)
Approach B: Create a list of Leg
objects and then put the combo_market_order, combo_limit_order, or combo_leg_limit_order method.
low_strike_put = next(filter(lambda x: x.strike == low_strike, puts)) middle_strike_put = next(filter(lambda x: x.strike == middle_strike, puts)) high_strike_put = next(filter(lambda x: x.strike == high_strike, puts)) legs = [ Leg.create(low_strike_put.symbol, -1), Leg.create(middle_strike_put.symbol, -1), Leg.create(high_strike_put.symbol, 1) ] self.combo_market_order(legs, 1)
Strategy Payoff
The bear put ladding is an limited-profit strategy. The payoff is
PlowT=(Klow−ST)+PmidT=(Kmid−ST)+PhighT=(Khigh−ST)+PayoffT=(Plow0−PlowT+Pmid0−PmidT+PhighT−Phigh0)×m−fee wherePlowT=Lower-strike put value at time TPmidT=Middle-strike put value at time TPhighT=Higher-strike put value at time TST=Underlying asset price at time TKlow=Lower-strike put strike priceKmid=Middle-strike put strike priceKhigh=Higher-strike put strike pricePlow0=Lower-strike put value at position opening (credit received)Pmid0=Middle-strikeTM put value at position opening (debit paid)Phigh0=Higher-strike put value at position opening (debit paid)m=Contract multiplierT=Time of expirationThe following chart shows the payoff at expiration:

The maximum profit is Khigh−Kmid+Plow0+Pmid0−Phigh0, which occurs when the underlying price is between the two lower strike prices.
The maximum loss is Khigh−Kmid−Klow+Plow0+Pmid0−Phigh0, which occurs when the underlying price decreases to $0.
If the Option is American Option, there is a risk of early assignment on the contract you sell.
Example
The following table shows the price details of the assets in the algorithm:
Asset | Price ($) | Strike ($) |
---|---|---|
Lower-Strike put | 3.80 | 822.50 |
Middle-strike put | 4.70 | 825.00 |
Higher-strike put | 7.80 | 827.50 |
Underlying Equity at expiration | 843.25 | - |
Therefore, the payoff is
PlowT=(Klow−ST)+=(822.50−843.25)+=0PmidT=(Kmid−ST)+=(825.00−843.25)+=0PhighT=(Khigh−ST)+=(827.50−843.25)+=0PayoffT=(Plow0−PlowT+Pmid0−PmidT+PhighT−Phigh0)×m−fee=(3.80−0+4.70−0+0−7.80)×100−1.00×3=67So, the strategy gains $67.
The following algorithm implements a bear put ladder Option strategy:
class BearPutLadderOptionStrategy(QCAlgorithm): def initialize(self) -> None: self.set_start_date(2017, 4, 1) self.set_end_date(2017, 4, 23) self.set_cash(100000) option = self.add_option("GOOG", Resolution.MINUTE) self._symbol = option.symbol # set our strike/expiry filter for this option chain option.set_filter(lambda x: x.include_weeklys().put_ladder(30, 5, 0, -5)) def on_data(self, slice) -> None: if self.portfolio.invested: return # Get the OptionChain chain = slice.option_chains.get(self._symbol, None) if not chain: return # Select the call Option contracts with the furthest expiry expiry = max([x.expiry for x in chain]) puts = [i for i in chain if i.expiry == expiry and i.right == OptionRight.PUT] if not puts: return # Select the strike prices from the remaining contracts strikes = sorted(set(x.strike for x in puts)) if len(strikes) < 3: return low_strike = strikes[0] middle_strike = strikes[1] high_strike = strikes[2] option_strategy = OptionStrategies.bear_put_ladder(self._symbol, high_strike, middle_strike, low_strike, expiry) self.buy(option_strategy, 1)