Publisher Item Identifier

The Publisher Item Identifier (PII) is a unique identifier used by a number of scientific journal publishers to identify documents.[1] It uses the pre-existing ISSN or ISBN of the publication in question, and adds a character for source publication type, an item number, and a check digit. These digits protect the privacy of the published item to ensure that it is not plagiarized.

The system was adopted in 1996 by the American Chemical Society, the American Institute of Physics, the American Physical Society, Elsevier Science, and the IEEE.


A PII (pii) is a 17-character string, consisting of:

  • one character to indicate source publication type: "S" = serial with ISSN, "B" = book with ISBN
  • ISSN (8 digits) or ISBN (10 characters) of the serial or book to which the publication item is primarily assigned
  • in the case of serials an additional two digit number to pad the difference between the 8-digit ISSN and an ISBN (suggested are the last two digits of calendar year of the date of assignment, which is not necessarily identical to the cover date)
  • a 5-digit number assigned by the publisher that is unique to the publication item within the serial or book
  • a check digit (0-9 or X)

When a PII is printed (as opposed to stored in a database), the 17-character string may be extended with punctuation characters to make it more readable to humans, as in Sxxxx-xxxx(yy)iiiii-d or Bx-xxx-xxxxx-x/iiiii-d.


  • Buscemi, Lara; Ramonet, David; Klingberg, Franco; Formey, Aurélie; Smith-Clerc, Josiane; Meister, Jean-Jacques; Hinz, Boris (2011). "The Single-Molecule Mechanics of the Latent TGF-β1 Complex". Current Biology. 21 (24): 2046–2054. doi:10.1016/j.cub.2011.11.037. ISSN 0960-9822. PMID 22169532. PII S0960-9822(11)01319-4.

See alsoEdit


  1. ^ Publisher Item Identifier as a means of document identification, Elsevier web site, last update 9 April 1998, accessed October 2003

External linksEdit