Negative discrete moments of the derivative of the Riemann zeta-function

We obtain conditional upper bounds for negative discrete moments of the derivative of the Riemann zeta-function averaged over a subfamily of zeros of the zeta function which is expected to be arbitrarily close to full density inside the set of all zeros. For k ≤ 1/2, our bounds for the 2k-th moments are expected to be almost optimal. Assuming a conjecture about the maximum size of the argument of the zeta function on the critical line, we obtain upper bounds for these negative moments of the same strength while summing over a larger subfamily of zeta zeros.