After replacing the oil filter, oil leaks out of the filter. Why?

Check to see if the old seal is attached to the filter housing, if two seals are present it will leak.

Does this vehicle have a canister type oil filter housing (ie.. paper filter instead of the more traditional metal style filter)? If it is the canister type with the paper filter, check the housing cap/cover (where the big o-ring seal fits into) for cracks or cross-threading. When you replaced the filter the second time, did you change the o-ring seals again with it? If not, it's worth a shot. Also, it's a VERY good idea to lube the o-rings with some engine oil before putting the housing cover back on. EDIT: just did some reading and found FRAM had a production run of O-rings that are too small and do not seal properly. If the oil is leaking between the housing cover and housing itself, I would try a different brand o-ring or better yet, one from the dealership. AND make sure to lube the o-ring with engine oil before re-installing the cap/cover.