There are no copyright marks seen on front or back of the photo.
A search for original copyright was done in the artwork category for the year 1928. While Pacific and Atlantic did register a good number of their photos taken in this year (unlike many of the other photo services), I've read the descriptions of all for P & A in 1928 and this photo was not among them.
To further confirm that there was no copyright, I did a renewal search in artwork for the years 1955 and 1956. There were no renewals for Pacific and Atlantic.
Based on the information above, this photo was never registered for copyright.
Licensing
Public domainPublic domainfalsefalse
This work is in the public domain in the United States because it was published in the United States between 1929 and 1977, inclusive, without a copyright notice. For further explanation, see Commons:Hirtle chart as well as a detailed definition of "publication" for public art. 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 the Graf Zeppelin landing at Lakehurst, New Jersey on October 15, 1928 following its first transatlantic crossing. |Source=[http://www.ebay.com/itm/1928-Original-Photo-GRAF-ZEPPELIN-LZ-127-Airship-DIRIGIBLE-1st-Trans...
File usage
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