The option ticker explains four main things about the option: the underlying stock, whether it is a call or a put option, the expiration month and the strike price. An option ticker is quoted by a series of letters. This is a lot of information crammed into one ticker, but we can help you decode option ticker symbols.
Option Ticker Structure
An option ticker can be broken down into three parts. The first part of the option ticker is the option symbol, which can vary in letter length. Typically, this symbol will be found on all the options of the company and will be identical to the stock symbol. However, this is not an absolute. For example, Microsoft's ticker is MSFT, while its option symbol is quoted as both MSQ and MFQ. The second part of the option ticker is the expiration date and the call or put classification of the option, and it consists of a single letter. There are 12 possible expiration periods for options  one per month. Options classified from A to L are call options and M to X are put options. The third part to the option ticker is the strike price of the option, and this is also a single letter. Because there is a wide range of potential strike prices and a limited number of letters, each letter represents more than one strike price. This creates the need for a bit of guesswork, but nothing overly complex.
Here is a visual breakdown of an Oct. 05 35.00 Merck Option:
To help you decode any option ticker, we are providing you with a code sheet:
Now that you have your option ticker code breaker, let's try an example:
GMIU  The last two letters provide information pertaining to the terms of the contract. This leaves the other two letters as the option symbol (GM). Again, the second part of the ticker (I) explains the month of expiry and whether it is a call or a put. Looking at the above chart, we see that this is a call option that expires in September. The third part (U) is a bit trickier: if we know that this is a General Motors option and the current stock price is $31.50, we can easily find that the strike price of this option is $37.50. By looking at the option ticker, we now know that it is a Sept. 37.50 GM call option.
When it comes to the strike price, it is important to remember that strike prices for most options do not vary a great deal from the current stock price. For example, it is rare that you would be able to purchase an option with a strike price of $500 that has a stock price of only $15.
Be warned that in the event of stock restructurings, like five for seven stock splits or mergers, there may be no way to use the codes above to find out information about the option. If such a restructuring occurs, the exchange on which the option is traded will change the option ticker symbol accordingly.
For further reading, see our Option Basics Tutorial.
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