The investigation centers on trades that may be linked to a correction in the company's subscription base, a spokeswoman for the watchdog told Reuters.
In October 2008, Premiere announced it was changing the method it uses for counting subscribers. As a result, its registered customer base fell by 940,000 compared to the previous classification.
At the end of the third quarter, Premiere said it had 2.4 million direct subscribers plus a further 704,000 wholesale customers.
The company told Reuters that it was aware of Bafin's probe but would not comment further while the investigation is in progress.
Premiere is currently implementing a restructuring plan that will see the company attempt to raise â¬525 million ($689 million) through two issues of new shares.
The subscription window for the second rights issue will close on April 17th.