We consider the problem of answering queries against a knowledge base (KB) using secrets, whenever it is possible to do so without compromising secrets. We study query answering against EL knowledge bases. We provide a polynomial time algorithm that, given an EL KB Σ, a set S of secrets to be protected and a query q or the form C(a) or r(a, b), outputs “Yes” whenever Σ q and the answer to q, to...
