Listserv was freeware from 1986 through 1993 and is now a commercial product developed by L-Soft, a company founded by Thomas in 1994.
[5][6] A free version limited to ten lists of up to 500 subscribers each can be downloaded from the company's web site.
[7] Several other list-management tools were subsequently developed, such as Lyris ListManager in 1997 (now Aurea Email Marketing),[8] Sympa in 1997, GNU Mailman in 1998, and Gaggle[9] in 2015.
[1] Some of the early software features allowed joining or leaving a list without the need for human administration.
The list owner could also add or remove subscribers, and edit templates for both welcome and system messages.
[15] 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.