Original copyright registrations were checked in artwork for the years 1958, 1959 and 1960. These years were checked because the news story says that the photo was taken in 1958. There were no listings for Associated Press in the three years examined. There's no evidence of copyright registration on the photo.
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.
{{Information |Description=Photo of Sir Laurence Olivier and Joan Plowright performing in ''The Entertainer'' on Broadway in 1958. |Source=[http://www.ebay.com/itm/LAURENCE-OLIVIER-The-Entertainer-theater-photo-lot-1960-/330725074691?pt=LH_DefaultDomai...