Appellation d'origine contrôlée (AOC) regulation dictate that the white wines from Gaillac must include at least 15% Len de l'El blended with Mauzac, though there has been movements to allow substitution of Sauvignon blanc (and since 2007 growers have been officially permitted to do so).
Like the Manseng family of grapes in the Jurançon, growers in the Gaillac region used the codification of wine laws for the Appellation d'origine contrôlée in 1938 to dictate a minimum usage of Len de l'El for all white blends produced in the area—thus sustaining its presence.
[6][7] While the laws were later amended in the 21st century to allow the substitution of Sauvignon blanc, the effects of the initial mandate for Len de l'El's use helped maintain the variety's presence in the region.
Incidentally, it is phonetically similar to the French translation loin de l'œil meaning "far from the eye" with the synonym sometimes still seen on wine labels along with other alternative spellings.
Therefore, growers tend to limit plantings of the grapes to hillside locations with well draining vineyard soils and ventilation of air currents to keep the vines dry.