taxes, ordinary income, and adjusted cost basis for RSUs
The sale of shares on vesting convolutes matters. In a way similar to how reinvested dividends are taxed but the newly purchased fund shares' basis has to be increased, you need to be sure to have the correct per share cost basis. It's easy to confuse the total RSU purchase with the correct numbers, only what remained.  The vesting stock is a taxable event, ordinary income.  You then own the stock at that cost basis. A sale after that is long or short term and the profit is the to extent it exceeds that basis.  The fact that you got these shares in 2013 means you should have paid the tax then. And this is part two of the process. Of course the partial sale means a bit of math to calculate the basis of what remained.