Cumulative companion fraction and corresponding binomial error regions plotted against the projected binary separation for cWR stars in our sample (blue) and O star primaries more massive than 25 M_⊙ (red) and 40 M_⊙ (orange) from the SMASH+ survey (Tramper et al., in prep.). The bottom horizontal-axis range is bound by the limits of the GRAVITY detection regime. The top horizontal-axis shows the orbital period for corresponding binary separations assuming a total system mass of 40 M_⊙. Furthermore, the black dotted line represents an interaction boundary for the relatively extreme case of M₁ = 40 M_⊙, q = 1 and e = 0.3. The gray shaded region spans the eccentricity range from e = 0 to e = 0.5. Also shown are a few WR binaries from literature approximately placed on the plot for illustration.