Checking a serial number isn't just about the date; it's about authenticity. Here are red flags that a serial number might belong to a counterfeit guitar:
During this period, Gibson stamped serial numbers that were somewhat chronological but notoriously inaccurate. They started at 100000 and went up.
On vintage instruments (1930s–1950s), you may find a separate FON stamped inside the body or on the neck block. Decoding Gibson Serial Numbers by Era Modern Era (1977–Present)
Next time you are at a pawn shop or browsing Reverb, pull out your phone, check the back of the headstock, and see if you can decode the history of the instrument yourself!