Because assets on the balance sheet are listed at cost, this means that there is no necessary connection between the total assets shown an the market value of the firm
The market value of a firm depends on things like its riskiness and cash flows, neither of which have anything to do with accounting.
Similarly, the shareholders’ equity figure on the balance sheet and the true market value of the stock need not be related.
For example, in 2014 the book value of IBM’s equity was about $20B, while the market value of the equity was $204B
For financial managers, then, the accounting value of the stock is not an especially important concern; it is the market value that matters