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The recently discovered 125 GeV boson appears very similar to a Standard Model (SM) Higgs, but with data favoring an enhanced h  →  γ γ rate. A number of groups have found that fits would allow (or, less so after the latest updates, prefer) that the $ht\bar {t}$ coupling have the opposite sign. This can be given meaning in the context of an electroweak chiral Lagrangian, but it might also be interpreted to mean that a new colored and charged particle runs in loops and reinforces the W -loop contribution to hFF , while also producing the opposite-sign hGG amplitude to that generated by integrating out the top. Due to a correlation in sign of the new physics amplitudes, when the SM hFF coupling is enhanced the hGG coupling is decreased. Thus, in order to not suppress the rate of h  →  WW and h  →  ZZ , which appear to be approximately SM-like, one would need the loop to ‘overshoot’, not only canceling the top contribution but producing an opposite-sign hGG vertex of about the same magnitude as that in the SM. We argue that most such explanations have severe problems with fine-tuning and, more importantly, vacuum stability. In particular, the case of stop loops producing an opposite-sign hGG vertex of the same size as the SM one is ruled out by a combination of vacuum decay bounds and Large Electron–Positron Collider (LEP) constraints. We also show that scenarios with a sign flip from loops of color octet charged scalars or new fermionic states are highly constrained.