George Fullerton and Leo Fender, started G&L Musical Instruments in 1980.
Around 1986, the meaning of G&L was changed from “George and Leo” to “Guitars by Leo”. This change was prompted by Leo[*].
[*Reference information provided by member GPD: http://guitarsbyleo.com/FORUM/viewtopic.php?f=32&t=8351]Guitars by Leo:
Around this same timeframe, the meaning of G&L was changed from “George and Leo” to “Guitars by Leo”. This change was prompted by Leo. Leo actually wanted to change the entire brand name, however, Dale saw no good reason to do this as it took years to establish the brand and all marketing, advertising, decals, and many hardware components would have to be changed with associated artwork and tooling costs to consider. Dale came up with the idea of changing the meaning so to avoid this cost and headaches…thankfully, Leo agreed. The trademark was indeed registered and if you called the office the phone was answered, “Hello, Guitars by Leo.” Some have refuted the reality of this but it indeed was the case.
In 1991, after BBE Sound, Inc. acquired G&L Musical Instruments, they reverted back to the original meaning of G&L to "George and Leo".
This is noted on the Certificate of Authenticity included with all standard production models.