I carry this Henckels 4 blade stockman pocketknife 99% of the time with me, except mine has a buffalo horn handle.
About 75% of the time I also carry my Gerber multi-tool, but that really can't be termed defensive, although it has a small blade.
About 10% of the time I carry my old and worn Buck 110, especially when hiking/fishing/camping/hunting. Served me well over the last 30+ years, and still in great shape as far as use, but I have so many things hanging from my belt I usually forgo it around town now.