It was reported (on American Movie Classics rotation of classic movies, back when they showed uninterrupted classic films) that all of the furs and jewelry used in this film were real and that guards were posted during shooting to ensure that none of the valuables disappeared.
$58,000, the price of the sable coat in 1937, would equate to over $1.18M in 2022.
The movie was the favorite of Italian director Bernardo Bertolucci's poet father. When the director came to visit New York City's Museum of Modern Art in the late 1960s, he asked their film department to screen their print of it for him so he could see it for himself.
Ray Milland actually got stuck in the tub while shooting the bathtub scene, according to director Mitchell Leisen. He kept the camera rolling and inserted the incident into the film.
The scene where Esther Dale as the secretary was based on director Leisen's own secretary who mixed up the several phones on her desk frequently.