For a graph property $$\varPi $$ , Subgraph Complementation to is the problem find whether there subset S of vertices input G such that modifying by complementing subgraph induced results in satisfying . We prove T-free graphs NP-Complete, for T being tree, except 41 trees at most 13 (a if it does not contain any copies T). This result, along with 4 known polynomial-time solvable cases (when pa...