This one is quite interesting and thanks to information in Don Maus' book, "History Writ in Steel: German Police Markings 1900-1936", prompted me to acquire this one, by way of an on-line auction. This pistol bears the front grip strap marking P.V.69. (Police-Verwaltung, weapon 69). Also, toe of magazine floor plate is marked 69.
In Don's book, Chapter 20 "Miscellaneous and Unidentified Markings", page 329, Table 20-14 he list an Ortgies serial 218752 bearing the marking, P.V.66. If I may quote, Don theorizes that P.V. may stand for Polizei-Verwaltung, (a generic term for Police Headquarters or Police Administration). Now two Ortgies are reported with the P.V. marking and only three weapon numbers apart!