Comment by FireBeyond

Yes, it's "I swear under penalty of perjury that it's my opinion that this infringes my copyright."

Creator's rights need to be safeguarded but the DMCA gives legal weight to people without legal training and when they fuck it up (accidentally or intentionally) they get the no-consequence "but it's just, like, your opinion, man, and no-one expects you to be a lawyer".