X amount of USCG personel can go to BUDS per year, mostly O ranks and they get attached to Teams and can cross over from USCG to USN. In reality USCG loses these people. The amount is miniscule and the SEALs are not about to be overrun by Puddle Pirates.
Sgt. Rafael Peralta ,United States Marine Corps Company A, 1st Bn, 3rd Marine Regt, 3rd Marine Divison
We will never forget your valor and sacrifice.
Semper Fi !
February 12th, 2011
My understanding is it's open to all ranks under the program but most have been O's thus far. Then they get absorbed into the NSW system for X number of months and are given the option of crossing to the dark side at some point.