Can two separate dependent claims be used to reject one claim in an obviousness-type double patenting rejection?

Question

Suppose an application is filed in the US with the following claim:

1. A widget comprising X and Y.

And the Inventor has another co-pending application claiming the same widget, but with X and Y recited in separate dependent claims like so:

1. A widget.
2. The widget of claim 1, further comprising X.
3. The widget of claim 1, further comprising Y.

Could the examiner properly reject claim 1 of the first application using “claims 2 and 3” of the co-pending application, i.e., with no other outside secondary reference? My gut instinct is no, because the co-pending application does not recite the subject matter of the first application in a single claim, but I can’t find anything in the MPEP to support this and I see these kinds of rejections being made by examiners left and right.

Answer 1

The standard is - are the claims “patently distinct” from each other.

This is like a 103 obviousness analysis (complicated, arguable and somewhat subjective) and therefore there would not likely be a hard and fast rule one way or the other about elements in separate dependent claims. If there was a rule it might go against your position.

If the widget can be usefully combined with X and the widget can also be usefully combined with Y it might be obvious that it can be usefully used with X and Y at the same time.

And, if the widget can functionally have X and Y together added to it then it might be obvious that either could individually be added to it.

You are free to argue that something about the nature of the widget, X and Y make using them separately and using them together are not obvious from each other.

If the claims were more alike you might get a statutory double patenting rejection that would be worse.

Note - in the first claim the widget is essentially just X + Y and in the second one a widget, by itself, has no X or Y. So the second claim widget isn’t the same widget as the first claim. In my answer I assumed the widgets were the same and therefore that a core widget was a Z, for example.