https://www.irs.gov/publications/p550/ch04.html#en_US_2014_publink100010601 A wash sale occurs when you sell or trade stock or securities at a loss and within 30 days before or after the sale you: Buy substantially identical stock or securities, Acquire substantially identical stock or securities in a fully taxable trade, Acquire a contract or option to buy substantially identical stock or securities, or Acquire substantially identical stock for your individual retirement account (IRA) or Roth IRA. 读了一下wash sale的定义 如果我同时买入和short同一支股票,只要等过了30天卖, 就不是wash sale了吧