I'd guess yours were wet enough to germinate. Normally they will be dry enough already if their pods are mature and dry on the vine, but some years you end up harvesting when the pods are wet. Those years, leave them spread out someplace dry and warm until they are. I use paper plates on the kitchen counter. I usually leave them out to dry for a while even if they seem dry.

Other than that beans are pretty easy as long as they are not a hybrid variety. Phaseolus sp. self pollinates but sometimes an insect will crosspollinate them, so save some seeds from several years so you can go back a year if one year the beans look or taste different.

Do you know what kind of beans they are?

I don't know. The beans that I first collected were from seeds that a friend brought back from China: broad beans of some sort. Since I found collecting them a bit of fun, I did the same with the rattlesnake beans. Most of both of them have sprouted, so I guess it's back to the catalogues.

Thanks for the reply!