This seems to be a problem similar to the one discussed in the thread that AgX is referring to ((there was a url link here which no longer exists)).
The scratches (on Foma 100-120) reported by me and others in that thread are a bit shorter and seem to have a different spread than yours on Foma 400-120. The cause may be the same though. The issue has been reported to Foma, who say they're working on it. Their response so far, through their Dutch distributor:
"I would like to inform you that we thoroughly investigated the sent samples and we tried to find the cause of resulting defect.
We didn´t find explicit cause in our production process, the defects occur randomly and very rarely.
As the cause appears a combination of our material with certain types of cameras (in some cases only).
One of the causes could be probably some minor impurities, whose rise by cutting wrappers (backpaper)
We made preventive measures to minimalize the possibility of recurrence of defects.
We believe that a coincidence, which caused these problems, wouldn´t negative affect our future cooperation."
and:
"For 120 Roll film: It seems to be that cameras with a tight loading system can have a problem. The scatches are very thin and a lot of people won't even notice them. Hasselblad 500CM, Mamiya RB and Rolleiflex TLR seems to be most sensible [sensitive] for the problem."
It will be useful if you report your problem to Freestyle. The more feedback Foma receives, the more likely they will be able and/or willing to fix this.