BASE is a multinational collaboration at the Antiproton Decelerator (AD) of CERN which aims at precise comparisons of the fundamental properties of antiprotons and protons. Such comparisons provide stringent tests of charge-parity-time reversal invariance which is the most fundamental symmetry in the Standard Model of particle physics. The BASE collaboration observed the first spin flips with a single trapped proton, measured the magnetic moment of the proton with a fractional precision at the ppm level, observed first single proton spin filps, and performed the first direct high-precision measurement of the magnetic moment of a single trapped proton. Our value has a precision of 3.3 ppb, outperforms previous Penning trap experiments by a factor of 760. In addition BASE performed the most precise test of CPT invariance with baryons, by comparing the antiproton-to-proton charge-to-mass ratio with a fractional precision of 69 parts in a trillion. Very recently BASE measured the magnetic moment of the antiproton with a fractional precision of 0.8 parts in a million and observed first single spin transitions with a single trapped antiproton.

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