As discussed in Section 2, the distributions of the route shapes for the set-n1 follow closely the distributions for the full set of routes extracted from the patent data. However, we also extracted a set of routes that are enriched in longer and convergent routes, which presumable should be a greater challenge to the search algorithms. For all three search algorithms, we indeed observe a decrease in the number of solved targets when comparing the predictions made on the set-n1 routes and the set-n5 routes (see Table ). Encouragingly, the decrease is typically rather small, between a fraction of percentage and a few percentages, for MCTS and Retro*. This shows that even though these algorithms require some more time to find a solution, they are capable of breaking down the compounds to starting material in stock. However, for DFPN, the decrease in the number of solved routes is on the order of 10%, a significant amount. This shows that DFPN not only is inferior to MCTS and Retro* in finding solutions but that its capabilities worsen with compound complexity.