Taken to the extreme, there would finally be 1 share left held by someone and thus that person would own 100% of the company and be entitled to 100% of the profits from said company. The company cannot just buy the last stock because the stock itself is worth all the cash the company holds and the future profits it will make. Saving up more cash to buy the final stock just raises the price because the stock is entitled to that cash and nobody is going to loan a company enough cash to be worth the expected future profits of said company which makes up the remainder of the shares value.
Funnily enough though, I think they would still do share buybacks by first splitting the stock and then buying a subset of the split stock because then the sole owner would only have to pay taxes on the sale price minus the price he paid for the stock whereas dividends are taxed in their entirety.
The last share is worth whatever the person that holds it is willing to sell it for, right? A share of IBM is worth $136 right now because there are two parties willing to buy/sell a share of IBM at that price.
I realize this would never happen in a million years, but could a company exist that is owned by nobody?
It’s not that unusual to have entities that essentially own themselves, in the sense that nobody is entitled to the profits and the board or managers elect their own successors. This is the case for foundations and trusts in many countries, usually with some kind of charitable purpose. Some of them even operate businesses. It might be possible for a company to take on some debt, buy out all its shareholders, and reorganize into a charity.
https://www.investopedia.com/terms/g/going-private.asp
One example is Dell: https://en.wikipedia.org/wiki/Dell#2013_buyout
Also see Elon Musk's infamous tweet about Tesla: https://en.wikipedia.org/wiki/Tesla,_Inc.#Securities_Litigat...
Interestingly, the company didn’t use buybacks to become private but it did use buybacks to become public again last year [1]. It was done by buying back some piece of its business that remained traded in the stock exchange following the acquisition of EMC when Dell was private [2].
[1] https://www.techspot.com/news/77848-dell-about-go-public-sec...
[2] https://www.bloomberg.com/opinion/articles/2015-10-13/dell-w...
But theoretically if a company do keep buying its own shares it can reduce their number to the point where the company is no longer required to be “public” and the shares can be delisted. However the important number is how many shareholders the company has, not how many shares (but obviously a company with 300 shares cannot have more than 300 shareholders).
I don’t know if that has ever happened. Reducing the numbers of shares (and shareholders) can also be done be reverse splitting. For example a company that is doing so badly that the share price goes to zero and regularly do inverse splits (making one $5 share from 100 $0.05 shares) will end up with a handful of shares. Or a company which is not failing may try to get rid of minority shareholders by doing reverse splits (if you don’t have enough shares to get the new one you get cash instead).
The usual way to reduce the number of shareholders is for someone to make a tender offer. And in that case there are rules about what happens with those who didn’t choose to sell. That’s what happened with Dell, that another comment mentioned, which was bought by Silver Lake.