Looks like snail damage to me.

May I ask where you got this Aloe? I've been looking for Helenae for awhile.

-Ron-

Ron, I live in Los Angeles and purchased this plant from the prior president of the Cacti club I belong to. He had a private sale open to club members only earlier in the year. I do not know what part of California you are in. It is kind of a shame, the Fullerton Arboretum just had a sale the first week of December and the same gentleman had 3-4 small Helenae for sale. If you are in the southern california area and must have one, I can inquire as to wether or not he has any more.
Thank you for the response to the post. You can email me privately if you want a photo of this plant or to exchange information.

Can't help as to what caused the damage to the leaf, but would you be so kind as to post a pic of the entire Aloe. I too am interested in that Aloe. Thanks

Desert Gardener - maybe later today, raining pretty good right now. To my horror, I looked into the yard today only to find one of my potted and flowering A. arborescens has identical damage on a leaf. It was not there yesterday, because I photographed the plant yesterday and it was not there. The snail hypothesis gains momentum. I thought maybe a fungal infection of some surface tissue. Any other aloes you would like photos of, weather permitting?