10-99B

You need to report every single sale. So not only do you have to separate it by brokerage account, you need to separate it by the actual sales (the "1099-B" you think is one form is really a consolidated 1099-B form where each entry is in reality a separate

1099-B. In old-fashioned times, you would get a separate, physical 1099-B for each separate sale you made).

Now, if you have some printout from the broker or from your own records which has all the information Schedule D wants, you can put lump sums on Sched D, write "SEE ATTACHED" and attach your printout to the return.

You list each sale seperately on one Schedule D, regardless of which broker you used. (I'm not sure what happens when you fill up Schedule D, you'll have to look at the instructions.) If you sold a security where some of the shares were held long term and some were short term, you would seperate that out onto 2 lines on Schedule D.

Best regards, Bob