n. A person whose wealth is derived solely from a single, well-performing stock.
Many of the wealthy are as concerned to protect their paper wealth as to borrow against it. For the southern rubbish collector, Warburg provided a combination of options called a zero-cost collar that is especially popular among the one-stock wealthy.
Merrill's move into social work is an example of how investment banks are serving one of their fastest-growing client groups, the one-stock wealthy — typically internet pioneers or entrepreneurs who have made billions by taking their companies public or selling them for shares.
Gareth Branwyn, Wired magazine's official jargon eyeballer, was kind enough to suggest this phrase.