这是一个关于 Bill Ackman 如何通过一次做空交易赚到 10 亿美元 的故事。 2002 年，Ackman 发布了一份针对市政债券保险公司 MBIA 的做空研究报告。他的核心观点包括： 市政债券保险并不是一个高利润的商业模式。 市政债券通常本身就有州政府背书，即便如此，保险的主要作用也只是降低债券的利率。从某种意义上说，保险费实际上是在侵蚀公共资金。 MBIA 的会计处理并未恰当反映其杠杆所带来的风险因素。 MBIA 的结构性金融产品存在严重问题。 MBIA 试图为 AAA 评级的 CDO 提供担保，而这些 AAA 评级本身，是华尔街与 MBIA 共同“制造”出来的。 一旦失去 AAA 评级，MBIA 的偿付能力将受到致命打击。 这份报告一经提出，立刻引发了大量质疑。甚至在报告正式发布前，MBIA 的董事长兼 CEO Joseph Brown 就私下约见了 Ackman，对他说： “你还很年轻，正处在职业生涯早期，在发布这份报告前，你应该三思而后行。我们是纽约州和纽约市债券最大的担保方，事实上，我们是全美最大的市政债务担保机构。换句话说——我们在高层有朋友。” Ackman 并没有退缩，反而选择了加倍下注。 他聘请了一位顶级的法务会计专家，并多次将 MBIA 存在欺诈性的会计证据提交给 Moody’s。 2005 年，Ackman 给穆迪董事会写了一封信： “穆迪的 AAA 评级极其强大、极具公信力，以至于投资者根本不会对底层信用进行尽职调查。只要穆迪每天错误地维持 MBIA 的 AAA 评级，这些极度厌恶风险的投资者，就会在不知情的情况下，购买那些并不配得上 AAA 评级的债券。” 除了直接做空 MBIA 的股票外，Ackman 还大量买入了 MBIA 债务的 CDS（信用违约掉期）。 可以把 CDS 理解为一种保险：当债务发行人发生信用事件或偿付风险时，买方获得赔付；作为交换，买方需要持续向卖方支付年度保费。 多年间，Ackman 为 MBIA 的 CDS 仓位支付的高额保费，严重拖累了他的整体回报。 终于，在 2008 年 2 月，MBIA 削减了股息，并暂停了其结构性金融业务。同年 6 月，MBIA 与 Ambac（当时最大的两家市政债券保险公司）一起，被穆迪剥夺了 AAA 评级。 这一刻到来时，Ackman 从这笔交易中 套现约 12 亿美元。 这个故事随后广为流传，也彻底奠定了 Bill Ackman 在对冲基金行业中的地位。 T2 Partners 的联合管理人 Whitney Wilson 曾这样评价他： “五年时间里，他一直是错的、错的、错的。 然后，他赚了数十亿美元。 他是这个星球上最顽固不化的人。” This is the story of how Bill Ackman made a billion dollars on a short position In 2002, Bill Ackman published a short thesis on municipal bond insurer MBIA. His thesis was > Municipal bond insurance is not a lucrative business model. Muni-bonds generally have guarantees from the state. Even then, insurance is only used to lower the interest rate on these bonds. In a way, insurance premiums were eating into the public money > MBIA’s accounting was not properly reflecting the risk factors tied to leverage > The structured finance products of MBIA were suspect. MBIA aimed to guarantee AAA-rated CDOs, but Wall Street and MBIA was manufacturing these ratings > The loss of AAA rating would significantly impact MBIA’s ability to remain solvent The report immediately attracted a lot of doubt. Before the report was even published, MBIA’s Chairman and CEO Joseph Brown privately met with Ackman “You’re a young guy, early in your career. You should think long and hard before issuing the report. We are the largest guarantor of New York State and New York City bonds. In fact, we’re the largest guarantor of municipal debt in the country. Let’s put it this way: We have friends in high places.” Ackman didn't back down; he doubled down and hired a top forensic accounting expert and brought evidence of MBIA’s fraudulent accounting several times to Moody’s. In 2005, Ackman wrote a letter to Moody’s Board of Directors: “Moody’s AAA rating is so powerful and credible that investors don’t do any due diligence on the underlying credit. Every day that Moody’s incorrectly maintains an AAA rating on MBIA, these extremely risk-averse investors unwittingly buy bonds that are not deserving of Moody’s AAA rating.” In addition to shorting the stock of MBIA, Ackman also purchased CDS, or credit default swaps, on MBIA’s debt The way to think of these swaps is insurance in the case of credit events or solvency risks that the issuer of the debt may face. In exchange, the buyer is forced to pay annual premiums to the seller The premiums that Ackman paid on his MBIA CDS position put a massive drag on his overall returns for many years Finally, in February of 2008, MBIA cut its dividend and suspended its structured finance activities. In June of the same year, MBIA and Ambac, the two largest municipal bond insurers, lost their AAA rating from Moody’s, and Ackman walked away with $1.2 billion of proceeds from the trade The story became widespread and cemented Bill Ackman's name within the hedge fund universe Whitney Wilson, Co-Manager of T2 Partners, wrote: “For five years he was wrong, wrong, wrong. Then he made billions. He is the most relentlessly stubborn person on the planet"