The court today convicted the 38-year-old man, identified only as Aydin C, for fraud and blackmail via the internet, according to a statement from the Dutch legal authorities.
It gave him the maximum possible sentence of 10 years and eight months, "because of the devastating consequences his behaviour has on the young lives of the girls" in particular, and out of fear that he could commit new offenses if released, the statement said.
In Canada, he faces a separate trial in the cyberbullying of Amanda Todd, a 15-year-old girl whose suicide drew global attention to online abuse.
A Dutch court has approved his extradition following his trial in Amsterdam. He has appealed that decision and denies involvement in any cyberbullying.
Todd brought cyberbullying to mainstream attention by posting a video on YouTube in which she told her story with handwritten signs, describing how she was lured by a stranger to expose her breasts on a webcam.
The picture ended up on a Facebook page made by the stranger, and she was repeatedly bullied, despite changing schools. She took her own life weeks after posting the video.