Final answer:
Copy 1 of DEA Form 222 stays with the supplier, copy 2 is sent to the DEA, and copy 3 stays with the purchaser.
Step-by-step explanation:
The DEA Form 222 is used to document the transfer of controlled substances between entities registered with the DEA. When a DEA Form 222 is used, copy 1 (the brown copy) remains with the supplier of the controlled substances. Copy 2 (the green copy) is sent by the supplier to the DEA as evidence of the transaction. Finally, copy 3 (the blue copy) is kept by the entity that originally ordered the controlled substances, serving as their record of the receipt and purchase.