a bagholder is a shareholder. left holding shares of worthless stocks.

The shareholders could be caught up in a corporate bankruptcy and accounting scandal, as was the case with Enron and Worldcom, or the victims of a pump and dump scheme, in which naive and unsophisticated investors fall victim to e-mail spam, rigged stock tip forums, or other tricks used by stock touts to drive.

The word is derived by combining the shareholder with the expression "left holding the bag."