How to obtain Amber24

Amber24 facilitates faster simulations (on parallel CPU or GPU hardware) and is distributed with a separate license and fee structure. Here is the license, which applies to all users, whether commercial or non-commercial:

AMBER24 Software License

GRANT OF LICENSE. The Regents of the University of California grants, and you hereby accept, a permanent, non-exclusive license to use the Amber 24 software product ("Software") to the extent of its rights and in accordance with the terms of this Agreement. This licensed copy of the Software may only be used by you and members of your organization at your site who have read and agreed to this license. You may install the Software on computers at your site, or at other locations, provided that reasonable steps are taken to restrict use of the software to you and members of your organization. You may not distribute copies of the Software to others outside of your organization, and may make only those copies of the Software which are necessary to install and use it as permitted by this Agreement, or are for purposes of backup and archival records.

OWNERSHIP. This ownership is protected by the copyright laws of the United States and by international treaty provisions. Upon expiration or termination of this Agreement, you shall promptly terminate use of the Software and accompanying written materials.

MODIFICATIONS AND DERIVATIVE WORKS. You may modify the software, and use it to create derivative works, for your internal use at the site covered by this license. You may not distribute such modified or derivative software to others outside of your site without written permission. You may distribute the modifications themselves (e.g. as "patches") under terms of your choice. We encourage users to contribute modifications back into Amber, but you are under no obligation to do so.

REPORTS OF PUBLICATIONS. You agree to acknowledge use of the Software in any reports or publications of results obtained with the Software.

ASSIGNMENT RESTRICTIONS. You shall not use the Software (or any part thereof) in connection with the provision of consultancy, modeling or other services, whether for value or otherwise, on behalf of any third party who does not hold a current valid Amber 24 Software License Agreement. You shall not rent, lease, or otherwise sublet the Software or any part thereof. You may transfer on a permanent basis the rights granted under this license provided you transfer this Agreement and all copies of the Software, including prior versions, and all accompanying written materials. The recipient must agree to the terms of this Agreement in full and register this transfer with the University of California.

LIMITED WARRANTY. LICENSEE acknowledges that LICENSORS make no warranty, expressed or implied, that the program will function without error, or in any particular hardware environment, or so as to generate any particular function or result, and further excluding any other warranty, as to the condition of the program, its merchantability, or its fitness for a particular purpose. LICENSORS shall not be liable for any direct, consequential, or other damages suffered by the LICENSEE or any others as a result of their use of the program, whether or not the same could have been foreseen by LICENSORS prior to granting this License. In no event shall LICENSORS liability for any breach of this agreement exceed the fee paid for the license.

UNIVERSITY OF CALIFORNIA'S LIABILITY. In no event shall the University of California be liable for any indirect, special, or consequential damages, such as, but not limited to, loss of anticipated profits or other economic loss in connection with or arising out of the use of the software by you or the services provided for in this Agreement, even if the University of California has been advised of the possibility of such damages. The University of California's entire liability and your exclusive remedy shall be, at the University of California's discretion, to return the Software and proof of purchase to the University of California for either (a) return of any license fee, or (b) correction or replacement of Software that does not meet the terms of this limited warranty.

NO OTHER WARRANTIES. The University of California disclaims other implied warranties, including, but not limited to, implied warranties of merchantability or fitness for any purpose, and implied warranties arising by usage of trade, course of dealing, or course of performance. Some states do not allow the limitation of the duration or liability of implied warranties, so the above restrictions might not apply to you.

Getting Amber24 for non-commercial use

Read the above license: note that it contains restrictions on usage and redistribution.

By filling out this form, you agree to the license, and confirm that all use will be non-commercial. Note that there is no license fee for non-commercial use.

The downloaded file, "pmemd24.tar.bz2", will be about 255 MB, and have an md5sum of 1b09b2edfa8f2d8698954855fa2c615f. Installation instructions are in Chapter 2 of the Amber 2025 Reference Manual. Follow the path called "pmemd24". More detailed instructions for many systems may be found at the OS-specific requirements page.

Note:There is a change from earlier version of Amber: the pmemd24.tar.bz2 file is self-contained, and does not require AmberTools code to be compiled and run. Many users can use the conda package to run AmberTools on local machines, and compile pmemd24 on a high-performance machine suitable for large calculations.

Getting Amber24 for commercial use

The license above is valid for both commercial and non-commercial usage. Only the license fee is different for commercial use. Commercial users should fill out this application for a commercial license. This will generate a license form that you can sign, and will contain information about how to pay the license fee. The form has a box for comments or questions you may have. Please direct all other correspondence concerning commercial licenses to AmberLicensing@ucsf.edu

Once payment is received, an email will be sent to the address you provide, containing a username and password, along with instructions on how to download the software.

Please note: The Amber24 license is a site license, valid for any number of users and any number of computers. The computers may be located anywhere (such as in the "cloud", or at remote computing centers.) Basically, the license deals with the affiliation of the users, and not with the location of the computing equipment itself.

Also note: Each release of Amber (which happens every two years) is treated as separate product, and requires a new license form and a new fee.

Fees:

• Academic/non-profit/government: $0. Use the "non-commercial" form, above.
• Industrial (for-profit): $25,000 for new licensees, $20,000 for licensees of earlier versions of Amber. For multi-site or multinational for-profit companies, there should be a license fee paid per site.  See the on-line order form for more information.
• Computing centers (operating on a not-for-profit basis) can license AMBER for a fee of $2000 and make executable code available to their users from non-profit organizations (no matter where such users are located, and irrespective of whether such users have their own Amber license). However, for-profit organizations who want to use the program at such centers must have obtained a separate license agreement with UCSF.
• Hardware manufacturers and compiler vendors who want to use the program for porting, benchmarking and demonstrations ONLY may pay $500.
• Users who licensed Amber22 after January 1, 2024 are eligible for a free upgrade to Amber24. (This is not automatic: if you wish to obtain the new version, you need fill out and submit a new License Agreement, indicating that you are eligible for the upgrade.)