HAMBURG-PACIFIC-DAMPFSCHIFFS-LINIE A.G.
image by Klaus-Michael Schneider, 8 April 2009
The flag is described as derived from Chile’s national flag, but with a white lower hoist quarter bearing dark blue HP above L in a triangular arrangement. Mathies also shows this form.
The Ships List version angles the letters. Rosanoski was unsure of the underlying source, since the linked memorabilia site did not display its flags to him; its accuracy therefore depends on that unidentified evidence.