[PPM]

Originally Posted by Lily8

Your terminology is somewhat inaccurate; there has been no 'ruling' as such. The term ruling implies that the matter has been considered by an authority and a decision was made. This, I believe, is not the case here. The online application form has been amended at some point; I believe this has happened as early as June 2018, though others have suggested October 2018. There has been no substantive decision on the matter, other than members of CBP advising members of the public that indeed their ESTA application should (now) include all first names and/or a middle name. What you refer to as an additional clarification has also been included on the online form as early as June 2018.

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Excellent. But does all that matter? ChrisS has been trying to tell everyone to put middle names onto ESTAs to comply with the form. It is now even clearer.
So, to summarise, if you are applying for an ESTA don’t forget middle name. It’s really that simple.