Can a closed way be included in two separate relations?

I’ve noticed one particular closed way, which is included in two different relations.
This one:

And this one:

In the first relation it represents an inner building area.

But what is the purpose of that second relation (2706065)?

Second one, with only a type=multipolygon and no other tagging is a mistake of some sort. Don’t know if it was ignorance or the particular editor the person was using. The item has only one version and it was done a number of years ago.

While it might be wrong in this case, in general it is possible that a closed way is part of 2 relations.
Imaging a lake on an island completely covered by a wood in a lake.
The outer lake is a relation with 2 ways LAKE (as outer) and ISLAND (as inner)
The wood would then be a second relation with that same ISLAND (now as outer) and the smallest lake as inner way.

This is also explained with images on

Thank you for the clear explanations both n76 and escada!