I've actually seen the same knife & stamp previously (and there's one currently for sale on eBay), so I'm pretty sure it's not a factory error or missing some dots. I have also seen the M1059L pattern with two other style date stamps, one was a 1995 and the other one was from the 2000 era, so my best guess for the date of your knife would be between 1990 - 1994.
For most of history, man has had to fight nature to survive; in this century he is beginning to realize that, in order to survive, he must protect it. Jacques Cousteau
For being a hero, get a bullet in the chest, O-U-A-T-I-T-W Mark Knopfler