The image was published as an advertisement in the U.S. in 1929. There is no evidence that copyright notice was originally filed on the image, as then required. For instance, this image evidently shows the entire poster and no copyright notice.
A search of copyright renewal records for 1956 and 1957 ([1], [2], [3], [4]) reveals no evidence that MGM/Loew's renewed copyrights to this poster or any collection of posters or any collection of material that might encompass this poster as would have been required to maintain copyright protection, if any.
There is no evidence that MGM claims copyright on the image.
Captions
Poster for the musical film "The Broadway Melody", 1929.