  In most versions of beyond the standard model (BSM) physics, the Yukawa
couplings of the quarks and charged leptons are not all to the same complex
scalar doublet but to different ones. Comparison to the standard model (SM)
with only one scalar doublet, using the known mass of the W boson, provides a
sum rule constraint on the Yukawa couplings $Y_i,~~ i=t, b, \tau,.....$ of the
form $\Sigma_i r_i^2 = 1$ where $r_i = Y_i^{(SM)}/Y_i^{(BSM)}$ and the sum is
over distinct scalar doublets. The LHC data on the branching ratios $H
\rightarrow \gamma\gamma, ~\bar{b}b, ~\tau^+\tau^-, ~etc.,$ allows detailed
comparison to this sum rule constraint and, as accuracy improves, will
constrain or exclude many BSM theories.
