Comment by thxg

Indeed those are the "big four" solver businesses in the West, and also probably the most reliably-good solvers. But by the time Gurobi withdrew from the benchmarks (a few weeks ago), COpt was handily beating them in the LP benchmarks, and closing down on them in MIP benchmarks. Solver devs like to accuse each other of gaming benchmarks, but I'm not convinced anyone is outright cheating right now. Plus, all solver companies have poached quite a bit from each other since cplex lost all its devs, which probably equalizes the playing field. So overall, I think Mittelmann benchmarks still provide a good rough estimate of where the SOTA is.