The "Private Collection" pipes are Preben Holm's most coveted pieces. They were crafted by the artisan himself from the late 1970's to the end of his career in 1986.

The stampings on the shanks are always displayed in the same order (see right). Information in white is systematically stamped, the one in grey is optional.

"Additional stampings" may sometimes occur under the carver's name (ie: "Traditional", "Fancy", "9m/m", ...)

The "C5" stamping appears on pipes distributed in the USA by CAO who took over distribution from Lane Ltd. in 1985. This distinguishing stamping was to avoid warranty issues with pipes that were not of CAO's distribution.

Gradings: The early Private Collection series were graded with 4 letters (ascending): A, B, C and D. Those letters may be encircled (older markings) or not.

Later, a "x0x" 5 tiers grading system was introduced (ascending): 101, 202, 404, 606 and 808.

Letter and x0x systems may coexist on the same pipe.

Stem logo:

Nearly all pipes of Preben Holm's Private Collection sport the carver's signature on their stem. It may sometimes be worn and in a very few cases it may be missing (replacement stem?). But Preben Holm's logos with the PH initials do not originally occur on Private Collection pipes.