I started to detect that trend about two months ago on Instagram. When and how did you first notice all these striped shirts popping up?

So we talked with Saunier to find out why he thinks this shirt has become the sensation of the summer - and what he’ll do with the account once the trend dies. And all summer, he’s been cataloguing these sightings, on the Instagram account which is emblazoned with the caption, “That striped shi(r)t.” But this repeating pattern of blue, yellow, and white stripes was ubiquitous enough to catch the eye of Thomas Saunier, a 30-year-old copywriter living in Paris.

They’re not a perfect match, since the Zara version has thick navy and mustard stripes, punctuated by white with no black. Then there’s a similar-looking shirt from Zara for a cool $40, about a fifth of the price of the original. The original button-up is French, of course: from Sandro, for $220, and available as a T-shirt for $79. Antoni, of Queer Eye fame, wore a matching set to a Netflix event, and Instagram influencers have been photographing this outfit around the globe, from Pride events in England to the coast of Italy. You’ve almost definitely seen that striped shirt this summer: a breezy button-up with yellow, white, black, and blue vertical stripes, often worn with the buttons mostly undone.

Red white striped button down shirt