As long as coin collecting has been a hobby, numismatists have enjoyed exhibiting and displaying their collections. With the advent of the internet, a new means of sharing collections has been developed: the online set registry. The two major third party grading services, PCGS and NGC, have created an internet-based database whereby collectors can input the details of their collections. In addition to basic details like the date, denomination, and grade of each coin, collectors can also upload photos and personal notes about each piece. Each registered set is then scored and ranked.

The scoring and ranking systems are based on two elements: completeness and quality. Some collectors aim to fill as many “holes” in a set as possible to attain a higher completeness score. Others prefer to have fewer pieces in their collection but focus on quality. In calculating the completeness score for a series, PCGS and NGC will usually just consider date and mintmark combinations. That is, they won’t penalize collections if they lack minor varieties.

In the numismatic marketplace, set registries have had a profound impact on collecting habits and values. Collectors can be competitive – and the desire to assemble a top-ranking registered set can generate wild auction prices. Sometimes the difference between a #1 and #2 ranking is owning one specific coin. If and when that particular coin is offered at auction (and multiple collectors need the coin to upgrade their registered sets), the result is a record selling price.

A common misperception is that only the wealthiest collectors can assemble a registry-quality set. PCGS has actually created a category called “Everyman Sets” whereby exceptionally complete sets in affordable grades are recognized and rewarded. Furthermore, many sets can be completed (even in high grades) for relatively little money. A collection of vintage United States gold coins might cost hundreds of thousands or millions to complete, but modern series like Jefferson Nickels or Franklin Half Dollars can be finished on a reasonable budget.

The set registry displays more than intact collections currently held by private individuals. In an effort to provide greater context, PCGS also lists collections impounded in museums as well as collections that have since been sold. Examples include the Smithsonian Institute (the most comprehensive United States coin collection currently intact) as well as the Eliasberg collection, which was the most complete group of American coins in private hands. Although the Eliasberg holdings were sold in a series of auctions in the 1980s and 1990s, PCGS has entered the collection onto the registry using estimated grades.