Bettmann does not usually hold the copyright to images donated to the collection, nor does it have copyright filings nor a copyright notice on any of their work before 1978. Getty does not hold the copyright to most, if any of their photos, a statement backed up by numerous lawsuits and court rulings.
Note that it may still be copyrighted in jurisdictions that do not apply the rule of the shorter term for US works (depending on the date of the author's death), such as Canada (50 p.m.a.), Mainland China (50 p.m.a., not Hong Kong or Macao), Germany (70 p.m.a.), Mexico (100 p.m.a.), Switzerland (70 p.m.a.), and other countries with individual treaties.
Uploaded a work by Unknown, dedicated to Bettmann Archive from [https://www.gettyimages.co.nz/detail/news-photo/minneapolis-minnesota-government-frank-g-clement-of-news-photo/517825192 Bettmann Archive/517825192/U1480087] with UploadWizard