Strange IB TWS

Discussion in 'Interactive Brokers' started by nitro, Apr 1, 2002.

  1. nitro


    I have a couple of option positions with IB.

    The P/L started fluctuating from $0, to -$200, to $-82.50, etc, without the price of the options changing once!!?? This went on for about 45 seconds, when it settled down to the correct value.

    Anyone experience this? Why would this happen?

  2. mjt


    When you say the option prices didn't change, do you mean that the quote didn't change? If so, then the fluctuation is probably due to the price of the last trade changing.

    For example, let's say you buy 1 contract for 1.25. The last price, until another trade happens after yours, will be 1.25. Your P&L will be 0. Then let's say a trade occurs on the bid at 1.00. The TWS software will calculate your P&L based on that price. So now your P&L column will show that you've lost $25, even while the bid and ask price have remained 1.00X1.25.
  3. nitro


    No! _NOTHING_ changed, _EXCEPT_ the P/L! Not the bid, not the ask, not the last!

  4. stevet


    so would it make sense in dollar terms if the p/l had changed relative to the ask and bid flipping - but for some reason the ask and bid quote did not change on your platform

    or might IB have some sort of filter on the quotes to your trading platform, that takes out rogue quotes, but their p/l calculation receive the rogue quotes
  5. nitro


    Yeah, further, _NOTHING_ else on IB is calculated with respect to bid/ask anyway.

    I don't follow you. _IF_ they were filtering quotes, then why would the P/L change? Unless you mean, they were filtering quotes, but the source code that does the P/L is not sharing in that filtering? Well that would certainly be a bug. Also, I have _NEVER_ seen IB TWS do this - it was bizzare.

  6. def

    def Sponsor

    2 things come to mind:

    1. the bid/ask might not have been updating on the exchange level but the internal theoretical price which calculates your margin was and was reflected in your pnl

    2. a program that calcs the pnls was restarted and it was just running through the old data till it caught up.

    i could be totally off base on this one but thats my 2 cents.
  7. nitro


    Happening again today, _BUT_, now I see that it is changing with the bid (/ask.)

    I have a theory. _IF_ the P/L is being calculated at the server, and that the quotes at the IB servers are updating correctly, _BUT_, somehow they do not update on the client (TWS,) this would explain (be consistent with) both this issue and the quote issues I am having.

  8. I am assuming that the P&L is calculated as the midpoint between the current bid and ask (at least that is what it looks like for my option positions that haven't traded at all).
  9. nitro


    Good question


  10. nitro


    I have quotes for half of the stocks that are opened, and it's 8:38. Where are those wonderful bulletins ?

    On the two options, I am "down" a hundred when I should be up a hundred, and on the other I am up $22.50 when I should be unch.

    #10     Apr 3, 2002