Search for B->pbar e nuebar X Decay using a Partial Reconstruction Method

Using data collected on the Upsilon(4S) resonance and the nearby continuum by the CLEO detector at the Cornell Electron Storage Ring, we have searched for the semileptonic decay of B mesons to electron-antiproton inclusive final states. We obtain an upper limit of B(B-> pbar e nuebar X)<5.9e-4. For the b->u decay, we find an upper limit of B(B^- -> p pbar e nuebar)< 5.2e-3. All upper limits are measured at the 90% confidence level.