I find it strange that whoever decided to do this kept the correct datecode on the packaging. Presumably they didn't label them as ATMega 328s until the order came in, it would have been trivial to change the datecode to something reasonable for that chip.
Years back, I talked to someone who had done some analysis on some of the "fake silver/gold" bars floating around places (I think they were common on Silk Road for a while?). Apparently some of the people faking metal bars didn't actually bother learning what a "Troy Ounce" was.
There was a "10 oz" bar that was 10 ounces - 283.5 grams. Except, in metals, "oz" means Troy Ounce - so it should have been 311 grams. You could literally feel that it was light if you were used to dealing with metals.
In the words of someone after they'd puzzled out the puzzle, "...so it looks like that die in the picture is pre-release engineering material. Where the hell did you find that?"
https://www.sparkfun.com/news/350
https://www.sparkfun.com/news/364
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https://www.sparkfun.com/news/395