Thanks to everyone for all the responses. They helped me solve the mystery of the open trunk lid problem. I usually carry the key in my pocket because I do not have any special fobs or other keys attached to it which makes it easy to carry around, yet probably easier to lose. As I was sitting at my desk in my home office, I realized that with just the right motion of sitting, standing, or crossing ones legs, the trunk activation button could easily be pressed against anything in my pocket or even a fold in my jeans. I took the key from my pocket and depressed the trunk button as a test, immediately running downstairs to the attached garage. Sure enough, the trunk lid was open and the doors were unlocked with the courtesy lights illuminating. I was surprised that the trunk button also activated the doors, but after a minute or so the doors automatically re-lock, and the lights slowly dim to totally off. The real surprise was that the key button worked from a distance of about 60 feet away and the second floor of my condo. The key looks to be of the original 2005 MY vintage, but I do have a spare which appears to be from the latest generation of Porsche 997 stock since it is heavier and in perfect mint condition. Now the key stays out of my pocket while at home which is a good idea anyway. I found that the friction created from sliding it in and out of my pocket wears off the red color of the Porsche badge on the key. At least that was my past experience with my previous 2001 996 Porsche keys. Hope this information may help someone else that has experienced the mystery of the open trunk lid latch.
