Numismatic Guaranty Company (NGC) is an international third-party coin grading and certification service based in Sarasota, Florida.

Along with CEO Steven Eichenbaum, Salzberg owns the CDN Greysheet, a price guide for coins similar to the Kelley Blue Book.

Similar to the ANA affiliation, this can be misleading as PNG dealers do not exclusively sell or endorse coins graded by NGC.

The certification process consists of authentication, grading, attribution, and encapsulation in plastic holders or Coin slabs.

[9][10] NGC certification offers significant protection against counterfeiting, misattribution, overgrading, and damage, but does not necessarily determine exact value.

In the May 26, 2003 edition of Coin World, the hobby newspaper had announced they had contracted investigators to conduct a year-long, comparative study of PCGS, ACCGS, and NGC, along with several other grading services, each known as Third Party Grader (TPG).

[12] NGC's label lists a coin's denomination, variety, grade, pedigree, serial number, and other info.

Using the label serial number, NGC will reveal a coin's date, denomination, grade, photo (if any), and pricing and Census info.