Meaning:

    “非” here is short for “非流通股,” which means “non-tradable stocks.” “大” and “小” mean “big” and “small.” “小非” refers to non-tradable stocks that account for less than 5 percent of the total stock capital and “大非” refers to non-tradable stocks that account for more than 5 percent of the stock capital. According to Chinese rules, the former can become tradable a year after the company reshuffling is completed or a new IPO, the latter will become tradable (5-10 percent) after two years and all the rest non-tradable stocks can be sold after three years.

    Example:

    A: 最近股市为什么跌的厉害？

    Zuìjìn gǔshì wèishénme diē de lìhài?

    Why is the stock market doing so bad lately?

    B: 可能大部分投资者还是担心大小非减持吧。

    Kěnéng dàbùfēn tóuzīzhě háishì dānxīn dàxiǎofēi jiǎnchí ba。

    Perhaps most of the investors in the market are worried that holders of non-tradable stocks would start a selling spree once their shares become tradable.