FYI,
Vanguard got back to a written question about how they handle UK beneficiaries
of US Vanguard IRAs and they say that they can open an account...but not a brokerage account.
So they can only hold US Vanguard mutual funds. This should not be a problem from a UK tax/reporting perspective
because the funds are wrapped in IRAs. Anyway here is what Vanguard says now.
"I wanted to reach out to you regarding your recent calls and questions
about having UK Residents as beneficiaries on your IRAs.
As it stands, your beneficiaries would be able to receive a portion of your
IRA as it is invested. A lump sum would not need to be paid out and I will
be informing the representative who told you this incorrect information
that this is the case.
While these beneficiaries cannot open a brokerage account, they would be
able to open an account type that only holds mutual funds in order to
receive their inheritance. They could then continue to buy and sell within
the account, provided that the UK continues to allow it and doesn't change
their laws.
As for your question about whether or not they could follow the 10 year
rule, I will want to defer this question to a tax specialist and/or an
estate attorney as we are not familiar with UK rules and regulations.
I hope this sheds some light on a previously unclear topic."