Dupicate Strikes

[Nereus]

New to options, I am wondering why a stock's options strikes will all the sudden have two of the same strike?

IE;
Calls <b>Strike</b> Puts

SIIEI 563 20 0.50 6.20 6.00 6.20 <b>45</b> 0.25 0.35 0.30 -0.10 20 2,388 SIIQI

SIIEW 1,464 7 0.40 4.00 3.90 4.20 <b>47.5</b> 0.70 0.85 0.75 -0.45 3 707 SIIQW

SIIEJ 666 2 0.10 2.50 2.30 2.45 <b>50</b> 1.50 1.65 1.45 -0.25 236 2,496 SIIQJ

SIIEX 0 0 0 <b>52.5</b> 0 0 0 SIIQX
SIKEX 46 11 0.40 1.40 1.15 1.25 <b>52.5</b> 2.85 3.00 2.80 0.08 13 380 SIKQX

SIIEK 0 0 0 <b>55</b> 0 0 0 SIIQK
SIKEK 37 1 0.34 0.55 0.45 0.60 <b>55</b> 4.70 4.90 4.54 -1.46 54 80 SIKQK

Also, note how not all the prices are duplicated.

I apologize if this is basic, but I searched and found no threads re: this issue.

Thanks greatly.

 

[nonprophet]

Note that X is used both for 22.5 and 52.5 strike:

http://biz.yahoo.com/opt/symbol.html

so e.g. SIIEX probably used to be a 22.5 call and is not used for the 52.5 strike, instead a new class SIK was created.

Providers show no data for SIIEX so the symbol may just be hanging in the system.

BTW, hopefully this kind of confusion will soon end:

http://www.theocc.com/initiatives/symbology/symbology_initiative_v1_2.pdf

 

[Nereus]

The symbol itself was not the confusing part. What I was getting at was that there was two duplicate strike prices.

50

50

55

55

etc... each with dif symbol and premium.


Finally found out that it may be do to a stock split. dunno for sure. I am to much a rookie to options.

Cheers

 

[demoship]

ANY contract adjustment may result in duplicate strikes.

ANY contract adjustment forces new "Standard" contracts to be created, and the old contracts that are now non-standard trade w/ different terms and symbols.

 

[spreadgod]

Quote from Nereus:

The symbol itself was not the confusing part. What I was getting at was that there was two duplicate strike prices.

50

50

55

55

etc... each with dif symbol and premium.


Finally found out that it may be do to a stock split. dunno for sure. I am to much a rookie to options.

Cheers

nereus,

the symbol itself is the part you SHOULD be concerned with. you are correct, what happened was there was a stock split and like prophet pointed out, the SIIEX used to be the 22.5 strike, and to avoid confusion they created a new root and made the symbol SIKEX. The quote vendors just never took out the SIIEX from the systems. check out this calendar for info about the option symbols and what they're actually derived from: