The 2026 ACL2 Workshop will be held in Menlo Park, California, USA, November 16-17, 2026, in a hybrid format: presenters can be in-person or remote, and both audiences will be able to watch all presentations. We invite users of ACL2, users of other theorem provers, and persons interested in the applications of theorem proving technology to attend.
Abstract submission: August 23 Paper submission: August 30 Author Notification: October 12 Camera-ready (author): November 2 Workshop: November 16-17 Possible tutorial day (TBD): November 18
The ACL2 Workshop series is the major technical forum for users of the ACL2 theorem proving system to present research related to the ACL2 theorem prover and its applications. ACL2 is an industrial-strength automated reasoning system, the latest in the Boyer-Moore family of theorem provers. The 2005 ACM Software System Award was awarded to Boyer, Kaufmann, and Moore for their work on ACL2 and the other theorem provers in the Boyer-Moore family.
ACL2-2026 will be held in Menlo Park, California, USA and also online, November 16-17, 2026. The workshop will take place in person at the SRI International headquarters. In addition to in-person participation, the workshop will support online participation for all talks and presentations. The workshop will be the 20th in the series of ACL2 workshops, which occur approximately every 18 months. It will feature technical papers as well as rump sessions that discuss ongoing research.
There will be two invited keynote talks.
We invite submissions of papers on any topic related to ACL2 and its applications, and we strongly encourage submissions related to other theorem provers or formal methods that are of interest to the ACL2 community. Suggested topics include but are not limited to new results in the following areas.
Submissions must be made electronically in PDF format. Submissions should be prepared in the EPTCS templates, available from http://style.eptcs.org, and submitted via EasyChair at:
https://easychair.org/conferences/?conf=acl22026
The ACL2 Workshop accepts both regular papers (up to sixteen pages excluding references) and extended abstracts (up to three pages excluding references). Both categories of papers will be fully refereed and need short abstracts submitted by the "Abstract submission" deadline. Accepted submissions in both categories will be included in the final workshop proceedings, although speaking slots will be shorter for extended abstracts. At least one author of each accepted submission must register for the workshop and give a presentation summarizing the paper's results. The presentation of the paper by the author may be done in-person or online.
Extended abstracts should contain at least one or two references so someone can pursue the abstract topic. Like regular papers, extended abstracts must describe work that has already been done -- it is not for ideas for future work. To discuss future work, we will have a rump session, and we will later appeal for those topics.
AI disclosure: If AI is used to write substantial parts of a submitted paper, the authors should mention that as a footnote to the title or in the authors part; it is to the authors’ discretion to decide what counts as ’substantial’, but for example small auto-completions should not count. If AI is used to perform part of the work described in the paper, it should be described in the text of the paper.
One of the main advantages of the ACL2 Workshop is that attendees are already knowledgeable about ACL2, its syntax, its basic commands, and the art of writing models in it. So authors may assume that readers have this familiarity.
Many papers presented at the workshop will describe interactions
with the theorem prover. Authors of such papers are required to
provide ACL2 script files
(typically, ACL2
books) along with instructions for their use with
ACL2, unless they provide a small text file explaining why
supporting materials are not appropriate (e.g., for a theory paper;
or, you can explain where to find supporting materials that are
already in the commmunity books). Such supporting materials should
have proper licenses and copyrights (feel free to email the workshop
chairs if you have questions about that). The books should be
certifiable either with custom instructions that are clearly provided,
or by running the following shell command in the directory of your
contributed books, where ACL2_DIR denotes your ACL2
sources directory and ACL2 denotes a recent ACL2
executable.
ACL2_DIR/books/build/cert.pl --acl2 ACL2 *.lisp
Send the supporting materials or (as discussed above) a small
explanatory text file to either Alessandro Coglio
(coglio@kestrel.edu)
or Sudarshan Srinivasan
(sudarshan.srinivasan@ndsu.edu).
For accepted papers, we will require authors to make these books available by adding them to the ACL2 Community Books. (Sol Swords may assist in that process, if asked.)
The workshop will also feature rump sessions, in which participants can describe ongoing research related to ACL2. Proposals for rump session presentations, including a title and short abstract, should be sent to the chairs. These proposals may be accepted until the workshop, but preference will be given to early submissions and subject to available time.
Feel free to email the Organizing Chairs if you have questions.
The workshop will take place at SRI International Headquarters, 333 Ravenswood Ave, Menlo Park, CA, 94025.
In addition, the workshop will be held online. Details of the online participation will be forthcoming.