To make the numbers simple, imagine a stock trades at $10/share. If someone came to you and said: how much would you be willing to pay to have an option to buy the stock for $100/share? The correct answer is: it depends. If it’s the right to buy the stock for $100/share at any point over the next 10 years then that’s worth more than to buy the stock at $100/share in the next day. A stock trading at $10 is unlikely to jump to $100 in a day so the option to by it for $100 is not worth much. It could happen, so it’s worth something. But it’s unlikely. So, again to make the numbers simple, let’s say it’s worth $0.01/option to buy a stock at $100 in the next day when it’s trading at $10 today.
Now imagine it’s the next day and the company with the $10 stock discovers the cure for cancer or invents time travel or perfects cold fusion. News breaks and now it’s trading at $1,000 per share. Now how much is the right to buy the stock at $100 per share worth? The answer is going to be something really close to, but maybe a small discount from, $1,000 (current value of the stock) - $100 (how much you pay based on the option) = $900. So what was worth $0.01 yesterday is worth $900 today.
Let’s say you have $10,000 to invest. If you know in advance the news is going to break you can do two things to (probably illegally) try and profit from it.
1. Buy 1,000 shares of the stock for $10/share. 2. Buy 1,000,000 options to buy the stock for $100/share tomorrow with each option costing $0.01.
With strategy 1 you spend $10,000 to buy something that, after the news breaks, is worth $1,000,000. Not bad. But with strategy 2 you spend $10,000 to buy something that’s worth $900,000,000 after the news breaks.
In both cases you’re likely to at least be investigated. And strategy 2 seems especially suspicious because the risk is so high and the non-illegal reasons for doing it are so few and far between. Very few reasons you’d buy a bunch of call options that only pay off if something causes a stock to move dramatically in 24 hours.
Finally, while short-dated, out-of-the-money call options are not something many if anyone should be playing with, they’re just a different flavor of something very familiar. To put it in context a lot of HN readers will understand more intuitively: a call option is what you often receive when you get equity in a startup. It’s the right to purchase shares at a price (strike price) before a certain amount of time (typically 10 years).
But why are they then legal to sell? It almost seems like someone wants to be able to sell them, but when they lose the bet they want to revert it. Free money if you're on the correct side.
Let's take a boring case -- that $10 stock is NOT going to $1000 tomorrow, they're not finding a cure for cancer, etc. So 99.9999999/100, if you sold someone the option for $.01, it's going to expire worthless tomorrow. You have 1M shares, you sell the call options for 1M * $.01 = $10,000.
You let some other people place bets on a thing that might (but probably won't) happen, and you get $10,000 just for owning the stock. It's like an interest payment (with some risk).
If the thing DOES happen, you are taking a risk that you'll have to sell your stock for slightly less than if you'd held it, so you're giving up some potential gains.
But in the long run, this is all priced out and balances out (in theory, in an efficient market). You get $10,000 in "interest" but are taking the risk that you might lose some upside in a black swan event, and the buyers are paying a nominal amount to take a bet on the other side. They might have spent $10k in order to possibly make a $billion -- those are risks that some people price and want to take (like a lottery).