We consider the two Higgs doublet model of type III which leads to flavor changing neutral currents at the tree level. In the framework of this model we can use an appropriate form of the Yukawa Lagrangian that makes the type II model limit of the general type III couplings apparent. This way is useful in order to compare with the experimental data which is model dependent. The analytical expressions of the partial width $\ensuremath{\Gamma}(\stackrel{\ensuremath{\rightarrow}}{t}{H}^{+}b)$ are derived and we compare with the data available at this energy range. We examine the limits on the new parameters ${\ensuremath{\lambda}}_{\mathrm{ij}}$ from the validness of perturbation theory.