The 32-year-old Swiss industry tastemaker and Pitt, 58, "have been dating for a few months," a source close to her tells PEOPLE.
The Oscar-winning actor and De Ramon, a representative of the jewelry brand Anita Ko, were seen together on Sunday at the Orpheum Theatre in Los Angeles for a Bono performance.
Furthermore, the insider claims that de Ramon, who divorced Vampire Diaries actor Paul Wesley earlier this year, is "very into" Brad.
The two "just started dating," according to a person close to Pitt, although the source further clarifies, "It's not an exclusive relationship
Along with married pair Cindy Crawford and Rande Gerber, Pitt and de Ramon were pictured backstage during the performance on Sunday.
De Ramon, a 2013 University of Geneva graduate who has previously worked for Christie's and the Swiss jewelry brand De Grisogono, wed Wesley, 40, in 2019.
Pitt has been married twice — to Jennifer Aniston from 2000 to 2005 and Angelina Jolie from 2014 to 2019 — and was recently linked to Emily Ratajkowski in late September.