If you look at the label of any piece of electronics that can radiate a signal (intentionally or not) you will see an FCC certification notice, and in some cases, a certification number. The certification number consists of a three-character grantee code and a one- to 14-character product code. FCC Rules generally require RF equipment to be authorized through certification, Declaration of Conformity, or verification.
Given the large number of manufacturers selling RF products in the United States, it isn't surprising the FCC was running out of three-character grantee codes. In Order FCC 12-60, the FCC expanded the grantee code from three characters to four characters.
The FCC news release announcing the Order explained the need for the additional character: “Applicants range from well-known companies like Gibson Guitar, Texas Instruments and Ford Motor Company, to seemingly unlikely participants such as Oreck, Adidas, and the Nebraska Furniture Mart, as well as numerous makers--large and small--of individual electronics components that are included in larger devices. The equipment authorization program is a key component of FCC’s spectrum and policy agenda. It encourages innovation in equipment design, ensures efficient use of the radio spectrum, and implements policy objectives such as the hearing aid compatibility of handsets.”
The announcement mentioned that rapid innovations in equipment design have caused an “ever-accelerating growth in the number of parties applying for equipment approval.” It noted that the FCC was now “running low” on identification code numbers for new applicants, and observer that the number of codes issued has increased from 954 in 2006 to 1,275 in 2011.
