Are you unofficially a PhD holder after passing viva voce for PhD? In my university, after passing a viva voce examination, it will take more than 3 months before the university issues an official letter/transcript/certificate to certify that one is officially a PhD holder. Of course, after PhD viva, it will take some time to perform correction as stipulated by examiners. It can be major/minor correction. After a PhD candidate passes viva exam, is she/he unofficially a PhD holder? Considering that one has yet to successfully correct one's thesis as instructed by examiners during viva exam.
At my American university, the process of officially getting a PhD was tiered.  It went something like this:


No claim to being a PhD until after successfully defending.
Some informal claim to being a PhD after successfully defending.  The committee members would usually make this explicit by congratulating the successful defendee with "Dr.".
A weird quasi-official claim when the university's official degree-completion tracking system formally acknowledged that the student has officially met all degree requirements and is scheduled to receive their degree at graduation.
Official claim upon graduation (whether or not attended).
Verifiable official claim once you have the piece of paper, which may be several weeks after graduation if not attended.


Folks I knew were reluctant to claim PhD-status until graduation, but I think that hiring managers in academia and industry tend to find the caveat of not having been through the ceremony to be fairly trivial.  Family and friends are especially unlikely to care about that caveat, except as an excuse to talk about how exciting graduation'll be.