I havent seen much of a difference as long as they are stored and cared for properly. Ive seen on some studies by NMSU that they can have a life of up to 8 years. The seeds are alive, but have a very very low metabolic rate. I have some seeds that Ive had for quite some time that I use to get some thais going every now and again that I got from a buddy working offshore that I had collect seeds and pods for me. They are going on 2 years old and I still get close to 90% of em up.