GPC rules

3) No foreign material (i.e.: fungicides, caulking, skin additives et cetera) will be permitted in the weighing of any fruit.
A) Vines must be trimmed to within one inch of the stem of the fruit.(a judge can trim it for you)
B) The stem itself will not be applicable to judging as stated below.
4) The specimen must be sound, healthy, and undamaged.
A) Entries must be free of rot.
B) Entries must be free of holes or cracks into the interior cavity of the fruit.
C) Entries must be free of damaged areas that are greater than 3 inches in diameter and greater than 3 inches deep. Any single damaged area greater than 3 inches deep will classify the fruit as damaged (DMG). The dimensions of the damage will be measured after all soft material has been removed with a spoon, if needed.

D) If there are more than two damaged areas, the pumpkin will be disqualified even if each is smaller than described in 4C.
E) Small damaged areas are acceptable if naturally healed over with new rind, also known as natural scabs or new cantalouping.
F) The Judges reserve the right to probe cracks, holes, and to dig out soft spots to judge a fruit official or not. Before the Judges can execute any of the previous they must have the grower present.
G) Judging is to be completed before a fruit is officially weighed.
H) Refusal of any inspection to an entry will cause the entry to be classified exhibition only.
5) The GPC will recognize one entry per grower or team for top ten average calculations.
A) Entries other than the grower’s one official entry will be entered as “EXH – exhibition” for legal fruit and “DMG – damaged” for illegal fruit.
B) If a grower or team wants to bring multiple entries they must contact the site representative(s) prior to the weighoff day to ensure the site can accommodate their multiple fruit.
6) No specimen will be allowed into competition at a GPC site if that specimen has been previously entered at another competition.

Full giant pumpkin information here