I discovered strange vertical lines on my negatives. They are about 1.5cm apart and visible on each negative. Sometimes one of this lines falls on a space between the frames.
Is it a light leak or a problem with a shutter? May be something else?
Camera - Leica MP. It has never had this problem before.
Thanks.

Does it extend the entire way across the negative, Past the sprockets?

If so, probably a light leak from the back door.

Ever-ready cases- the last defense against a light leak...

Yes, they do extend all the way across the negatives.
Probably you are correct.
Thank you.

Do the lines get closer together as the roll progesses? Could be a light leak in the film canister, the distance decreasing as the circumference of the film on the roll decreases. Just a thought.