If you were to sell a brokered CD before maturity, you have a capital gain or loss. You should also note going into the transaction that selling brokered CDs may carry a significant cost to you, and I would not consider them "liquid." Meaning, the price you get for the sale of the CD may not be favorable. In general, you should commit to holding brokered CDs until maturity.
If you buy a secondary issue or sell a new issue before maturity, you may have a capital gains or loss. You'll also have accrued interest that's added to or subtracted from your 1099INT (you create an adjustment on Schedule B).
most likely all the info you'll need for tax reporting will be on the 1099-B the broker sends you but you may have to dig into all the details since most brokers now issue consolidated 1099s so the data will be in different places.
