Here are a few LP/MIP solvers that are (somewhat) new to me:
Google's GLOP
This is an LP solver and part of OR-Tools [1]. The license is Apache v2.
HiGHS
An LP+MIP solver under active development by Julian Hall e.a.[2]
"HiGHS is a high performance serial and parallel solver for large-scale sparse linear programming (LP) and mixed-integer programming (MIP) models developed in C++11, with interfaces to C, C#, FORTRAN, Julia and Python."
MIT license, Successor to Clp?[3] Interesting to see the reference to John Forrest's "Idiot Crash".
MindOpt, Copt
I don't know much about these two solvers[4,5]. They are commercial and both are from China.
It is great to see some optimization tools from Asia. Until now things were largely US- and Europe-based.
MIPCL
There is also an LP/MIP solver that seems to be no longer available[6]. Some users showed good performance with this solver.
References
- The Glop linear solver, https://developers.google.com/optimization/lp/glop
- HiGHS, https://www.maths.ed.ac.uk/hall/HiGHS
- Julian Hall, HiGHS, High-performance open-source software for linear optimization, https://co-at-work.zib.de/slides/Montag_21.9/HiGHS%20slides%20(1).pdf
- MindOpt, https://solver.damo.alibaba.com/htmlpages/page#/en
- Copt, https://www.shanshu.ai/copt/
- Nicolai Pisaruk, http://pisaruk-9591.appspot.com/
- H. Mittelmann, Benchmark of Simplex LP solvers, http://plato.asu.edu/ftp/lpsimp.html