????美國(guó)國(guó)家經(jīng)濟(jì)研究局（National Bureau of Economic Research）本周發(fā)布的最新研究報(bào)告《以退為進(jìn)》（Winning by Losing）由加州大學(xué)伯克利分校（the University of California, Berkeley）的教授進(jìn)行。報(bào)告的結(jié)論是，雖然收購(gòu)幾乎總能贏得投資者的掌聲，但最終會(huì)對(duì)公司（特別是股價(jià)）造成負(fù)面的影響。報(bào)告指出，收購(gòu)方的股價(jià)在收購(gòu)后三年的漲幅往往比同類公司落后50%。研究還發(fā)現(xiàn)，（通常被認(rèn)為更保守的）現(xiàn)金收購(gòu)結(jié)局往往比換股收購(gòu)更糟糕。如果被收購(gòu)公司不愿意接受收購(gòu)方的股票，投資者自然也不愿意。

????失敗的并購(gòu)案例不勝枚舉——《財(cái)富》雜志（Fortune）母公司時(shí)代華納（Time Warner）在互聯(lián)網(wǎng)鼎盛時(shí)期的一宗收購(gòu)尤其如此。不過(guò)，盡管失敗的并購(gòu)不在少數(shù)，但經(jīng)濟(jì)學(xué)家們通常認(rèn)為并購(gòu)有益于公司。說(shuō)到底，如果沒有好處，為什么會(huì)出現(xiàn)這么多的并購(gòu)交易？大多數(shù)并購(gòu)，至少?gòu)氖召?gòu)方而言，一般都獲得了良好的市場(chǎng)反響。更重要的是，很難驗(yàn)證如果不收購(gòu)，情形會(huì)怎樣？你怎么知道如果不進(jìn)行收購(gòu)，這家公司會(huì)有怎樣的表現(xiàn)？

????為了回答這個(gè)問(wèn)題，加州伯克萊分校（Berkeley）的兩位教授烏爾里克?瑪門迪爾和恩里克?莫萊蒂以及阿姆斯特丹大學(xué)（University of Amsterdam）的一位教授佛羅瑞?彼得斯對(duì)熱門的競(jìng)購(gòu)交易進(jìn)行了分析，比較了競(jìng)購(gòu)成功者與失敗者的股票表現(xiàn)。結(jié)果發(fā)現(xiàn)，盡管收購(gòu)前股價(jià)走勢(shì)相似，但收購(gòu)后的走勢(shì)卻出現(xiàn)了分化，競(jìng)購(gòu)成功者的股價(jià)表現(xiàn)遠(yuǎn)弱于競(jìng)購(gòu)失敗者。

????或許人們會(huì)說(shuō)，這是因?yàn)楦?jìng)購(gòu)激烈，收購(gòu)方不得不提高出價(jià)，導(dǎo)致最終的交易不太理想。但三位教授比較了競(jìng)購(gòu)交易和無(wú)競(jìng)購(gòu)交易，結(jié)果發(fā)現(xiàn)最終的收購(gòu)估值都差不多。一宗收購(gòu)有可能因?yàn)槭召?gòu)價(jià)過(guò)高而導(dǎo)致最終結(jié)果不理想，但如果是這種情況，它是所有的收購(gòu)都可能存在的問(wèn)題，不光是競(jìng)購(gòu)交易。

????這對(duì)華爾街意味著什么？金融危機(jī)期間，投資銀行因?yàn)檫^(guò)去的很多行為備受指責(zé)。有人質(zhì)疑，將按揭貸款分割出售究竟給市場(chǎng)經(jīng)濟(jì)增加了什么價(jià)值?；蛟S首先要提到的就是按揭債券。但一旦華爾街開始根據(jù)打包的按揭貸款抵押資產(chǎn)、出售CDS，要給經(jīng)濟(jì)增加價(jià)值？沒門。如果說(shuō)有什么成果的話，那就是因?yàn)槿A爾街的這些交易，市場(chǎng)經(jīng)濟(jì)以及99%的人們?nèi)兆佣即蟛蝗缜傲恕Ｍ瑯?，我們并不清楚投行的并?gòu)業(yè)務(wù)是否給市場(chǎng)經(jīng)濟(jì)帶來(lái)了真正的價(jià)值。好消息是，沒有證據(jù)顯示是投行在拉郎配。往往是首席執(zhí)行官們自己樂于投身這類前景堪憂的并購(gòu)。但不管怎樣，華爾街都是同謀，而且從中撈到了大量的油水。

????Beware of Wall Streeters bearing mergers and acquisition advice. That's the takeaway of a new study, and investors should take note as well.

????The study by professors at the University of California, Berkeley, concludes that acquisitions, while nearly always initially cheered by investors, end up hurting a company, and in particular its share price, in the end. Winning by Losing, which was released this week by the National Bureau of Economic Research, found that following an acquisition the stock of that company tends to underperform shares of similar companies by 50% for the next three years. Another finding of the study: Deals done in cash, which is often considered a more conservative way to pay for acquisitions, tend to do worse than deals done for stock. If an acquiring company doesn't want its new owners' shares, you shouldn't either.

????There are tons of examples of deals that have gone south - the one done by Fortune's parent company Time Warner at the height of the dot.com frenzy was a particular doozy. But despite the many bad deals, economists have generally thought mergers are beneficial for companies. Afterall, why would so many of them get done. Most deals, at least from the acquirers' perspective generally get a good reception in the market. What's more, proving otherwise is a hard thing to do. How do you know how a company would have performed without the deal?

????To get around that problem, the two Berkeley professors, Ulrike Malmendier and Enrico Moretti, and a professor from the University of Amsterdam Florian Peters looked at situations where there were hotly contested acquisitions. They then compared the winners of the acquisition bidding war to a similar company that had lost out. What they found is that while the shares of the pairs of companies had tended to perform rather similarly before the acquisition, after the deal the prospects of the two companies diverged, with the company that had made the acquisition performing much more poorly than the company than did not.

????You could argue that in contested bids acquirers tend to be pushed to pay more, and therefore end up with a worse deal than usual. But the professors compared what was paid in the contested deals they looked at and acquisitions where there hadn't been multiple bidders and found that the valuations put on the acquired companies were about the same. So an acquisition may fail because the acquiring company overpays, but if that's the case, that's a problem with all deals, not just when there is a bidding war.

????What does this mean for Wall Street? I-banks have been criticized for many of the things they did during the financial crisis. Some have questioned whether the dicing up of mortgages added any value to the economy. Perhaps on the first go around with mortgage bonds. But once Wall Street got to creating credit default swaps on synthetic tranches of mortgage collaterlized debt obligations, no way. If anything, the economy and the 99% ended up worse off because of all those Wall Street deals. Here, too, it's not clear the I-banks' M&A business is adding any real value to the economy. The good news is that there is no evidence that bankers are pushing companies to do these deals. CEOs are more than happy to launch into ill-fated combinations all on their own. Nonetheless, Wall Street is complicit in the game, and makes plenty of money off it.