I don't think that's always correct. Quoting from the cost basis portion of one of my combined 1099 packets: > Note: This information is not reported to the IR

I don't think that's always correct. Quoting from the cost basis portion of one of my combined 1099 packets: > Note: This information is not reported to the IRS. It may assist you in tax return preparation. They give me a 1099B that's all zero cost basis, then in a different part of the paperwork bearing that disclaimer give me a "supplemental" 1099B that includes cost basis. Dunno why, but the CPA I asked said it was all above-board and to calculate cost basis off of the supplemental info.