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We measure the red giant branch bump (RGBB) of the Galactic bulge, the mostmetal-rich RGBB ever detected. The RGBB luminosity functions peaks at theexpected brightness, but its number density is very low relative to Galacticglobular cluster calibrations, implying the Galactic bulge has a higher heliumenrichment parameter {\Delta}Y/{\Delta}Z $\ge$ 4.0 for Y~0.35 rather than thestandard 2.0 with Y=0.27. The RGBB is (0.71 +/- 0.02) mag fainter than the redclump (RC) in I toward the densest stellar regions imaged by the OGLE-IIIGalactic bulge photometric survey, (|l| $\le$ 4, 2 <~ |b| $\le$ 4). The numberdensity of RGBB stars is (12.7 +/- 2.0)% that of RC stars. The brightnessdispersion of the RGBB is significantly lower than that of the RC, a resultthat is difficult to explain as the luminosity of the RGBB is known tosignificantly vary with metallicity. Sightlines toward the Galactic bulge thathave two RCs have two RGBBs with similar properties to one another, an expectedoutcome if the Milky Way's bulge is X-shaped. We also find preliminary evidenceof the Galactic bulge asymptotic giant branch bump, at a brightness of ~1.1 magbrighter than the RC in I and with a number density ~1.5% that of the RC.Accounting for the RGBB has a small effect on the best-fit parameters of theRC, shifting its best-fit peak brightness and reducing its brightnessdispersion by ~0.015 mag each.

OGLE-III Detection of the Anomalous Galactic Bulge Red Giant Branch Bump: Evidence of Enhanced Helium Enrichment