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MICROSCOPE's final results report no violation of the Weak EquivalencePrinciple (Universality of Free Fall) for Pt and Ti test masses quantified byan E\"otv\"os parameter $\eta\simeq10^{-15}$, an improvement by about twoorders of magnitude over the best ground tests. The measurement is limited byrandom noise with $1/\sqrt{\nu}$ frequency dependence attributed to thermalnoise from internal damping occurring in the grounding wires. From informationavailable and the physics of internal damping we calculate the differentialacceleration noise spectral density at the signal frequency, and show it varieswidely between experiment sessions. Such large variations are inexplicable iftranslated into physical quantities such as the quality factor. Whilecalibrations interspersed with measurement sessions may cause some suchchanges, they cannot explain jumps between consecutive sessions withoutrecalibration. A potential explanation is conjectured related to a fluctuatingzero depending on measurement initialization errors. The experiment wasseverely affected by "glitches" -- anomalous acceleration spikes related toradiation from the Earth -- injecting significant power at the signal frequencyand its harmonics. The procedure used to deal with the glitches depends onintroducing artificial data and leaves spurious effects potentially mimicking aviolation signal or canceling a real one. An alternative procedure, relyingonly on real measured data, is proposed, already used in ground tests of theWeak Equivalence Principle by the E\"ot-Wash group. Future experiments aimingto exploit the full potential of space must resolve these issues, rely solelyon measured data, and, more generally, readdress the experiment design.

Anomalies and open issues of the MICROSCOPE Space Test of the Weak Equivalence Principle