What Is an Acquisition Number?

An acquisition number is a unique identifying code that provides information about when an object was added to a collection such as a museum, library, or similar resource. Organizations typically have their own code for acquisition numbers, and when an object changes hands, it will be assigned a new number. This is part of collections management, the art and science of maintaining accurate, detailed, and useful records on objects in inventory for the benefit of researchers, owners, and other interested parties.

The number of digits in an acquisition number can vary, and the number may break down into several segments, each of which offers coded information beyond the time at which the item entered a collection. For example, a library might use codes that start with a year, include a two digit code specifying the type of item, and then add three or more digits to indicate the individual acquisition number. A number like 200912304, for example, might indicate that the item was acquired in 2009, is an academic journal, and was the 304th journal to be added to the collection in that year.

Some collections use the term “accession number” instead. In either case, this identifying code is one of the first items associated with objects when they come into the possession of the organization. A technician who processes the item on arrival will generate an acquisition number, add it to the item's record, and tag it, if possible. This could involve placing a sticker or transmitter on the item, or creating a curatorial card to go with it if the item cannot be handled directly.

It is possible to look items up by acquisition number as well as other parameters, if this is of interest. These numbers can provide valuable information to observers who know the code associated with them. They also allow organizations to quickly sort databases to organize inventory in a meaningful way. A biostatistician, for instance, might sort fields to highlight all proteins added to a database in a given year.

Acquisition code systems are designed to be flexible, to allow room for expansion of collections and events like entering a new century, where a double digit year code might cause confusion. In a museum that has been open since the 1700s, for example, a year code like “18” might indicate any number of years, like 1918 or 2018. In the event the system needs to be revamped to accommodate changes to the nature of an organization's work, this can result in a lengthy recoding process to accurately enter older items in the collection under the new classification system.