The W.R. Case & Sons Cutlery Company has a very rich history that began in 1889 when William Russell (“W.R.”), Jean, John, and Andrew Case began fashioning their knives and selling them along a wagon trail in upstate New York. The company has produced countless treasures and it continues to do so as one of the most collected brands in the world.
It's definitely post 1989, so sometime in the 1990s or 2000s (it's not particularly old, if that's what you're trying to determine). You may need to contact Case Customer Service if you want to know the exact year this "undated" tang stamp was used. Sorry I can't be more helpful.
I'm gonna make a guess that it's late 1990s. As Q says, it's not real old, as evidence by the "lightning s" (wasn't used earlier than 1980) and shape of the tail of the C says 1990s to me. http://www.wrcase.com/case_college/tang_stamps/ There may be a dot or two hidden under the bolster. Don't see that pattern much so not sure where the dots were located on those blades. Or maybe that one just didn't get stamped with the dots.
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"Discernment is not knowing the difference between right and wrong. It is knowing the difference between right and almost right." - Charles H. Spurgeon https://www.akti.org/
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.