Embargo (academic publishing)
In academic publishing, an embargo is a period during which access is not allowed to certain types of users. The purpose of this is to protect the revenue of the publisher.
Various types exist:
- A moving wall is a fixed period of months or years. (See below.)
- A fixed date is a particular time point that does not change.
- A current year (or other period) is setting a time point on Jan. 1 of the current year, so that all material earlier than that is available. Although fixed during the year, it will change each year.
There are various purposes:
- In delayed open access, the embargo separates the most recent period, for which a subscription is needed, from an older period, where a subscription is not needed and anyone may access the article. This is usually between 2 months and 5 years.
- In full-text databases, such as those of EBSCO Publishing or Proquest, it separates the most recent period, where only a title or abstract is available, from an older one, which is openly accessible. It also separates the relatively recent period for which sometimes only a low-quality copy, such as ASCII is available, from an older one, which may have higher quality versions, such as PDF.
 Moving wall
In academic publishing, a moving wall is the time period between the last issue of an academic journal available in a given online database and the most recently published print issue of a journal. It is specified by publishers in their license agreements with databases (like JSTOR), and generally ranges from several months to several years.