商场如战场，并购也不能幸免。在并购中，收购公司可以用四种颜色的骑士来表示：

黄衣骑士（Yellow Knight）

A yellow knight is a company that was making a hostile takeover attempt, but then backs out and proposes a merger with the target company instead. Often, this change of heart occurs after they realize that the target is going to cost more and/or has better takeover defenses than expected. Suddenly the yellow knight might find itself in a weak bargaining position, forcing it to walk away or propose a friendly merger as an alternative.

曾经尝试恶意收购，但最后与目标企业商讨合并机会的公司，称为“黄衣骑士”。这种改变通常是因为“黄衣骑士”意识到收购目标企业成本较大，或者目标企业采取了行之有效的反收购策略，从而使“黄衣骑士”发现己方在谈判中处于弱势，最后不得不开始谈判比较让人接收的条款。

黑衣骑士（Black Knight）

Black knights make unwelcome, hostile takeover bids and, unlike yellow knights, stand their ground. These types of predators are the source of nightmares for target company management as they bully their way into power and usually have goals that deviate from what the current bosses are trying to achieve.

黑衣骑士亦称黑色骑士，是指某些袭击者通过秘密地吸收目标企业分散在外的股票等手段，对目标企业形成包围之势，使之不得不接受苛刻的条件，把企业出售，从而实现企业控制权的转移，这些袭击者即称为“黑衣骑士”。

白衣骑士（White Knight）

The opposite of black knights, white knights are the friendly forces tasked with rescuing the target from the clutches of another prospective buyer with intentions to bleed it dry to make a quick profit.

Often, company officials will seek out a white knight to preserve its core business or to negotiate better takeover terms. The white knight might agree to play this role in exchange for some incentives, such as paying a smaller premium to take control than otherwise would be required under competitive bid conditions.

当公司成为其他企业的并购目标后（一般为恶意收购），公司的管理层为阻碍恶意收购的发生，去寻找一家“友好”公司进行合并，而这家“友好”公司被称为“白衣骑士”。一般来说，受到管理层支持的“白衣骑士”的收购行动成功可能性很大，并且公司的管理者在取得机构投资者的支持下，甚至可以自己成为“白衣骑士”，实行管理层收购。

为了吸引友好公司来与恶意收购者竞价并最终击退后者，处于被收购威胁中的目标公司通常会与这家友好公司达成一些协议。当然，这些协议都是尽可能地使“白衣骑士”从中获益。

灰衣骑士（Grey Knight）

Grey knights, as their color suggests, sit somewhere between white and black knights. Though not as desirable as the former, they are at least viewed as a more appealing option than the latter.

Grey knights capitalize on the fact that they are perceived as a friendlier alternative to a hostile black knight and use that as a negotiating chip to get a more favorable deal when a persistent, unwanted predator comes calling.

“灰衣骑士”介于“白衣骑士”与“黑衣骑士”之间，是敌是友尚难判断。虽然不及“友好”的“白衣骑士”，但相较于充满敌意的“黑衣骑士”，“灰衣骑士”更具有吸引力，可以作为谈判筹码，从而达成更有利于己方的交易。

参考：

1. Investopedia

2. 百度百科