The easier case first. Domestic partners have nothing to worry about since they would be covered by the Roommate Law, if nothing else. You can *always* have a roommate sharing your apartment, regardless of what the Proprietary Lease may say.

The case of the woman who moved in to take care of her now-deceased parents is more difficult, and you should absolutely consult an attorney. The shareholders are no longer occupying the apartment, which means you'll need to check the Proprietary Lease. Most commonly, the relevant portion is Paragraph 14, "Use of Premises." The classic test is whether it says the permitted occupants are "the Lessee AND ..." or just "the Lessee, ..." In the past, the "AND" case has been held to require concurrent occupancy by the shareholder, though there have been some cases challenging this. Again, the advice of an attorney is required.

Frankly, though, it seems ludicrous and more than a little obnoxious to try to press such a claim after the shareholders have been dead for a decade. In fact, if the circumstances were known to the board the whole time, I would imagine the woman's attorney could argue that the board tacitly consented to her occupancy and it's too late to press their claim.