[jimmydddd]

You can patent an improvement or tweak to a previous product. E.g., someone could patent a pencil, then someone could patent a pencil with an eraser, then someone could patent a pencil with a pyramid-shaped eraser. So they possibly are trying to patent some small inprovement to the older product.

[nikitaga]

Then the copycats can bypass your tweak patent by not implementing your tweak.

In theory. But having a patent lets you sue your competitors in a very expensive way for them, even if they win by invalidating your patent as straightforwardly as the legal system allows.

Funny how that works. I guess when the OP said you need a lawyer, it was more of a threat than friendly advice.

[jimmydddd]

Agreed.