在工商业上，白武士可以是指向另一间公司提供协助的公司、私人公司或者个人，可以分为几类。

一类的白武士是向遭受第三方恶意收购的公司提出善意收购。白武士进行收购的目的是为了阻止第三方以较差的条件或价钱收购目标公司的权益。白武士可以提出更好的条件或价钱，以抬高收购价格，或击退进行恶意收购的公司。

简而言之，若目标公司“Q”正在遭受恶意公司“R”的收购，“白武士”公司“P”向“Q”提出善意的收购。

另一类的白武士，向一间垂死的公司提出收购，而该公司不一定是正在面临恶意收购。该公司可能严重负债、甚至可能已经破产。在这个情况下，白武士收购这间公司要承受很高的风险。收购后，白武士会重组该公司，或与该公司合并。

In business, a white knight is a friendly investor that acquires a corporation at a fair consideration with the support from the corporation's board of directors and management. This may be during a period while it is facing a hostile acquisition from another potential acquirer (black knight) or it is facing bankruptcy. White knights are preferred by the board of directors (when directors are acting in good faith with regards to the interest of the corporation and its shareholders) and/or management as in most cases as they do not replace the current board or management with a new board, whereas, in most cases, a black knight will seek to replace the current board of directors and/or management with its new board reflective of its net interest in the corporation's equity.