The Maple series of SAT solvers are a family of conflict-driven clause-learning SAT solvers for solving the Boolean satisfiability problem. The key innovation of these solvers is the use of the learning rate branching heuristic (LRB), a departure from the VSIDS branching heuristic that has been the status quo for the past decade of SAT solving. Note that the experiments in our SAT 2016 paper describing LRB use only pure branching heuristics. That is, the VSIDS experiment uses only VSIDS and the LRB experiments uses only LRB. The hybrid LRB-VSIDS branching heuristic in MapleCOMSPS and MapleGlucose is only for the SAT competition and not part of the SAT 2016 paper.
Disclaimer: The term Maple in MapleSAT is in honor of Canada. We have no connections whatsoever to the MapleSoft company, which incidentally is also located in Waterloo and has strong links to the University of Waterloo.