The men, based at RM Condor on the outskirts of Arbroath, Angus, are accused of public indecency in a nightclub on June 2.
Each denies a charge of committing graphic sexual acts in the smoking area of DeVito’s in Millgate. They face trial in September.
It is understood the service will not convene a court martial if it is aware there is a civilian court case pending, but the allegations have been investigated.
The men deny any wrongdoing, but a Marines source said the allegations alone are “enough to raise questions about 45 Commando” at a time when servicemen and women need to be “unimpeachable” following a high-profile trial last year, which heard newcomers were made to drink from mess tin filled from a paddling pool containing urine and vomit.
Jordan Coia, Ben James, Michael Byrne, Ryan Fowler, Luke Bowen, Jacob Holt and Craig Lynch are accused of one charge of public indecency in the smoking area of DeVito’s nightclub in Millgate on June 2, comprising acts such as exposing themselves, urinating in public, drinking each other’s urine, smacking bare buttocks, and committing acts of a graphic sexual nature.
“It is not like the old days where lads got leave and did what they wanted to blow off steam,” the source said.
“The world is watching us and we need to be whiter than white.
“Higher-ups have cracked down on initiations, and rightly so.”
A Royal Navy spokeswoman said: “While legal proceedings continue, it would be inappropriate to comment further”.
The men appeared on an undertaking before Sheriff Jillian Martin-Brown, and trial was set for September 25.
Lynch, 42, Holt, 21, Bowen, 25, Fowler, 23, Byrne, 26, James, 22, and Coia, 22, whose addresses were given at Forfar Sheriff Court as c/o RM Condor, deny the single charge on summary complaint.
Not guilty pleas were entered by local solicitors Angela McLarty, Grant Bruce, Ian Flynn, Lynne Sturrock, and Michael Boyd.