Embargo

Embargo is a restriction on access to the content of a copy of a work for a defined period of time. In open access publishing, an embargo most often applies to a repository copy of the author accepted manuscript: the manuscript is deposited (see deposit) and its metadata (title, authors, abstract) is made publicly visible immediately, but the full-text file itself stays hidden until the embargo’s end date.

How embargo length is set

Embargo length is set by the publisher’s self-archiving policy (or, less commonly, by a funder or repository’s own governance policy) and varies widely by publisher and discipline — commonly ranging from zero (immediate access) to 6, 12, 24, or 36 months, and occasionally longer in some fields. The period is counted from a date of start of embargo that the policy defines — typically date of online publication, date of acceptance, or date of deposit — through to the date of end of embargo. CASRAI’s guide to checking a journal’s self-archiving policy with Open Policy Finder covers how to look up the specific embargo terms attached to a given journal.

The shift toward zero-embargo funder mandates

Embargo length has been a major point of tension between publishers (who use embargoes to protect subscription revenue during a work’s most commercially valuable early period) and funders pushing for faster public access to publicly funded research. Several major funders have moved to eliminate embargoes outright for recent award cohorts:

• The US NIH’s 2024 Public Access Policy requires Author Accepted Manuscripts accepted for publication on or after 1 July 2025 to be deposited in PubMed Central with zero embargo — available at the article’s official publication date — replacing the up-to-12-month embargo the prior NIH policy allowed.
• The US Department of Energy’s 2023 Public Access Plan similarly moved from an up-to-12-month “administrative interval” to zero embargo for publications from 1 October 2024 onward.
• cOAlition S’s Plan S has long required, as one of several compliance routes, deposit with no embargo (or a maximum embargo where a compliant fully-OA route is unavailable) for its member funders’ grantees.

A journal’s embargo terms should always be checked directly rather than assumed, since practice still varies substantially across publishers, subject areas, and funder-negotiated agreements — an embargo that once ran to 24 months at a given publisher may have since shortened, or a newer funder mandate may override it entirely for a specific author’s grant.

Embargoes on metadata vs. full text

Most embargo policies restrict only the full-text file, while allowing the record’s metadata — title, authors, abstract, journal citation — to remain publicly visible and discoverable from the date of deposit. Some repositories or funders additionally embargo the metadata itself for a shorter period (for example, where an invention disclosure or patent filing is pending), though this is far less common than a full-text-only embargo.

Worked example

A publisher’s self-archiving policy sets a 12-month embargo on the accepted manuscript, counted from date of online publication. An author deposits their accepted manuscript in their institutional repository on the publication date; the metadata is visible immediately, but the full-text PDF stays hidden from public download until 12 months later.

Counter-example

A press embargo — the media-relations practice of asking journalists not to publish coverage of a forthcoming paper before a set release time — is a related but distinct use of the word “embargo”: it restricts pre-release news coverage timing, not ongoing repository access to the manuscript itself.

Frequently Asked Questions

What triggers the start of an embargo?

The publisher’s self-archiving policy defines this — most commonly date of online publication, though some policies use date of acceptance or date of deposit instead. See date of start of embargo.

Are embargoes going away?

Several major funders — including the US NIH, the US DOE, and cOAlition S’s Plan S members — have moved toward requiring zero-embargo deposit for recent award cohorts, but embargoes remain standard practice at many publishers outside those specific mandated routes.

Does an embargo hide a deposited work from search entirely?

Usually not. Most embargo policies restrict only the full-text file; the record’s metadata (title, authors, abstract, citation) typically remains publicly visible and discoverable from the date of deposit.

Is a publisher embargo the same as a press embargo?

No — a press embargo restricts when journalists may publish news coverage of a forthcoming paper, unrelated to repository access restrictions on the manuscript file itself. See press embargo.