This may be a bit advanced for newbies so if feel free to post up any questions (no matter how noob). This discussion will be based on plain vanilla american-style options for the FX market which expire daily at 10am NY time. There are options like European, exotics, and all on a decentralized FX market so this is never a simple thing to understand
With that said… If spot price of a security is close enough to a large vanilla option heading in to the NY cut (10am in New York or 1400 GMT), it will often act as a magnet from selling taking place above strike and buying done below. The order flow generated could be from banks hedging as price approaches a strike where their clients will need to be paid out, or from large option holders exercising their right to buy/sell after price as gone in-the-money which could send price back past the strike level. There are two sides that need to trade, and if the option is large enough, there will be enough trading done to actually move the market.
Its important to note that after the 10am NY option cut, that day’s options will expire and the gravitational pull it had won’t be there anymore.
Here’s an example of Eur/Usd’s price action on Sept 26th… News of a large option expiring today Large options for today’s NY (10:00am ET) cut: EURUSD at 1.3500 from Forex dealers, and how price reacted:
That Eur/Usd option was worth over “1 yard”, 1 yard=1 billion US$. Large options that have a big affect will usually be over $500million or ‘half a yard’. Keeping up with whats going on in your chosen market can save a great deal of guessing and can really give you the advantage to trading against uninformed traders I’ve been using this free news feed for order info as of late: Order Flow Trading News
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Here’s the Gbp/Usd on Oct 4th reacting to a large option at 1.6050: GBPUSD option expiry at 1.6050 for today’s NY cut
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