Shalesha Kinney, 26, and Alek Tarr, 30, both of the Colbert Avenue address, and Deshaun Scott, 20, of Braddock, were taken into custody at about noon, Oil City police said.
All three were charged with felony counts of possession with intent to deliver heroin, criminal conspiracy to deliver heroin, possession of a controlled substance and criminal use of a communication facility.
They were arraigned before district judge Andrew Fish and placed in the Venango County jail.
Kinney and Tarr were lodged on $25,000 bail, and Scott was placed in jail on $35,000 bail.
A preliminary hearing for all three defendants has been tentatively scheduled for Wednesday in Central Court.
More arrests are expected in the investigation, police said.