AA3 pocket watch?

Is this what you call the AA3 pocket watch which predates the AA4 and official longines watch? Would longines have records of the AA3 as well?

No. It is nothing to do with Longines. Same name and occupation, but Geneve is not Jura area surrounding St. Imier where the Longines E.Francillon is from. I made same mistake and have some Ernest Francillon. Longines historian said different person. It could be that this is the reason E.Francillon created the Longines logo because of the confusion caused by this competitor Ernest Francillon.

Longines has no records prior to AA4. Extremely difficult to get authentic pre-AA4. It's a gamble with lots of misinformation and false advertisers due to the confusing marketings of early watches.

Ah thank you understood. Yes very confusing to have exact same name.

Also because they are both using Robert Japy ébauche. So movement is the same. It's all about who assembled the watch and which comptoir made it. Dangerous territory. I don't think I know of any authentic AA3 except in the Linder book. I think even Longines can not tell you if a watch is a AA3, but they can tell you if it isn't a Longines JAPY AA3, that is easier to do. Again no records of pre-AA4