Assessable Stock
A class of stock in which the issuing company is allowed to impose levies on stockholders for more funds. In the past, there was no restriction on how much additional money a company could demand or on how often a company could impose a levy on its stocks.
These are the opposite of non-assessable stocks.
Taobiz explains Assessable Stock
Before the twentieth century, assessable stocks were the prevalent type of equity that companies would issue. In order to entice investors into buying this potentially expensive stock, issuers would initially sell the stock at a discount.
For example, an assessable stock has an initial capitalization of $20, but the issuer would sell the stock with a 75% discount ($5). Naturally, seeing how the issuer only received a small fraction of the capitalization, companies would almost always come back to investors for more money. In some cases, companies would eventually take more money than the value of the stock.
However, because all stocks issued today are non-assessable stocks, investors should not have to worry about a company making demands for more money.