INTRO Here's my semi-annual exercise to see if I remember why I own the stocks I own, and so I can check back and see if their stories have changed. I post in case it helps others too.GeronGERN (market cap $0.523B)Geron is a highly speculative biotech stock because its great potential also entails great risk. The company is pursuing a number of technologies: stem cells, nuclear transfer, telamorase management. All of the technologies are innovative and powerful, but they will also require more than the usual amount of testing, and regulatory agencies typically act more slowly with innovations.The company has progressed nicely by having initiated clinical trials, but as was seen in 2009, trials can be stopped and delayed for months when unexpected phenomena arise.The ability to significantly extend life through organ repair, organ replacement, and cancer treatment, point towards impressive potentials, but all applications and subsequent revenues are years away.I will continue to hold because of the promise and would consider buying more if funds became available, which ironically are most likely to come from the sale of another biotech stock (DNDN). I will also curb my enthusiasm though because of the long road to FDA approval ahead of them.DISCLOSURE LTBH since 1999.