||This article appears to be written like an advertisement. (March 2012)|
|This article relies on references to primary sources. (March 2012)|
|Original author(s)||Eric Thomas|
|Stable release||16.0-2011a / November 8, 2011|
The term Listserv (written by the registered trademark licensee, L-Soft International, Inc., as LISTSERV) has been used to refer to a few early electronic mailing list software applications, allowing a sender to send one email to the list, and then transparently sending it on to the addresses of the subscribers to the list.
The original Listserv software, the Bitnic Listserv (also known as BITNIC LISTSERV) (1984–1986), allowed mailing lists to be implemented on IBM VM mainframes and was developed by Ira Fuchs, Daniel Oberst, and Ricky Hernandez in 1984. This mailing list service was known as Listserv@Bitnic (also known as LISTSERV@BITNIC) and quickly became a key service on the BITNET network. It provided functionality similar to a UNIX Sendmail alias and, as with Sendmail, subscriptions were managed manually.
In 1986, Eric Thomas developed an independent application, originally named "Revised Listserv" (also known as "Revised LISTSERV"), which was the first automated mailing list management application. Prior to Revised Listserv, email lists were managed manually. To join or leave a list, people would write to the human list administrator and ask to be added or removed, a process that only got more time-consuming as discussion lists grew in popularity.
By 1987, the users of the Bitnic Listserv had migrated to Thomas' version.
Listserv was freeware from 1986 through 1993 and is now a commercial product developed by L-Soft, a company founded by Listserv author Eric Thomas in 1994. A free version limited to ten lists of up to 500 subscribers each can be downloaded from the company's web site.
Automated Mailing List Management 
In 1986 Eric Thomas invented the concept of an automated mailing list manager. Whilst a student in Paris he developed the software now known as Listserv. Some of the early software features allowed joining or leaving a list without the need for human administration. Also, the list owner could add or remove subscribers, and edit templates for both welcome and system messages. Amongst other innovations Listserv introduced double opt-in in 1993 and the first spam filter in 1995.
After the release of Thomas' Listserv in 1986, Listserv@Bitnic was enhanced to provide automatic list management, but was abandoned a few months later when Bitnic installed Thomas' Listserv.
During that period North Carolina State University had been given a copy of the Bitnic code to run on their mainframe (LISTSERV@NCSUVM). This was actually a modified version of the code with improvements from Alan B. Clegg. NCSU switched to Thomas' Listserv in 1986. Other than their name, Bitnic's and Thomas' products are unrelated and neither product is based on the other product's code.
Listserv was registered as a trademark with the U.S. Patent and Trademark Office in 1995, based on its use since 1986. It was registered with the Swedish Patent and Registration Office, PRV, in 2001. As such, in those jurisdictions, using the word "listserv" to describe a different product or as a generic term for any email-based mailing list of that kind is a trademark misuse. The standard generic terms are electronic mailing list, elist, or email list for the list itself, and email list manager or email list software for the software product that manages the list. Nevertheless, the generic use of the term has been common at times.
Through version 15.0, individual user passwords were stored in the clear, and available to users who are listed as Site Managers or "Postmasters" in the application configuration, thus allowing unethical managers, or attackers who compromise the site, to easily try to reuse the username and password on other sites. Passwords are hashed to protect against this since version 15.5, which was released in 2007.
Listserv is available in several licensing options: LISTSERV Lite Free Edition for non-commercial hobby use; LISTSERV Lite for smaller workloads; LISTSERV, the standard, full-featured version; LISTSERV HPO (High Performance Option); and LISTSERV Maestro (for customized and targeted email publishing and reporting).
Supported operating systems 
See also 
- "Unedited archives of LSTSRV-L, LISTSERV site administrators' forum, July 1986-".
- "Costello Sam. "E-mail lists get virus protection", CNN.com, Sci-Tech, October 30, 2001".
- "CV of Eric Thomas".
- "L-Soft web page with download links for the free version, LISTSERV Lite Free". Retrieved 12 April 2013.
- "History of the Internet — 1986".
- "Listserv product history timeline".
- "Bitnet Network Information Center announcement by Judith Molka on the NODMGT-L List, January 7, 1987".
- "History of LISTSERV@BITNIC and LISTSERV email list management software, 1985-1995".
- Lambert, Greg (June 2009). "Where Do Listservs Fit in a Social Media World?: The networking tool of the 90s is starting to show its age". AALL Spectrum 13: 8,9,13.
- "LISTSERV Trademark Registration at USPTO".
- "PRV, the Swedish Patent and Registration Office".
- "LISTSERV trademark information".
- "What’s New for LISTSERV". 2007. Retrieved 2012-03-08.