这倒塌关于硅谷银行这是美国历史上第二大银行倒闭案，发生在不到48小时内。
上周一天之内，客户就提取了420亿美元，接近该银行存款总额的四分之一。
快速的银行挤兑引发了人们对金融机构在数字环境中脆弱性的质疑，这种环境的特点是现金提取容易，信息在社交媒体和其他在线空间传播，少数人的恐慌可能会发展成为蜂拥退出。
专家告诉美国广播公司新闻，这种被称为数字银行挤兑的可能性增加了突然、大范围现金提取的风险，特别是在一群共享一个行业和社会联系的储户中——就像硅谷银行的储户。
“这是第一次推特引发的银行挤兑，”众议院金融服务委员会主席、共和党众议员帕特里克·麦克亨利在一份声明硅谷银行倒闭后的几天。
硅谷银行的储户群体由相对较少的风险投资公司、科技初创公司和其他大型投资者组成。
在上周三一份令人沮丧的财务报告引发担忧后，一些储户在WhatsApp和致力于创业的Slack小组中讨论了他们的反应华尔街日报举报。
与此同时，几位知名风险投资家和其他主要投资者在Twitter上表达了他们的担忧，加剧了对崩盘的担忧。
因预测次贷危机而闻名的投资者迈克尔·伯里在一份报告中警告说现已删除的推文:“今天我们可能找到了我们的安然。”
周四，由于担心硅谷银行陷入困境的财务状况，该行股价下跌了60%。
据企业家亚历山大·托雷内格拉(Alexander Torrenegra)说，到下午早些时候，这家银行的突然衰落接管了初创企业创始人之间的在线讨论。
托雷内格拉说:“我与美国科技创始人的所有聊天记录都点燃了正在发生的事情。”详细叙述在推特上。“显然，我们有一个银行决胜。超现实。”
由亿万富翁投资者彼得·泰尔领导的风险投资基金Founders Fund当天取出了所有存款，彭博举报。
由于该银行有联邦存款保险公司的保险，储户在银行倒闭的情况下，可以从不同类型的账户中获得高达25万美元的资金保障。然而，硅谷银行的许多储户持有的账户金额远远超过25万美元，这加大了那些未能在潜在银行倒闭前取出资金的人的风险。
杜克大学金融学教授坎贝尔·哈维(Campbell Harvey)对美国广播公司新闻(ABC News)表示:“因为信息出来得更快，所以你可以实时获得信息，它是广泛的，它会引导人们采取行动。”“如果你是第一个出局的人，你会得到100%的奖金，如果你是最后一个出局的人，你可能会一无所获。”
美国大学华盛顿法学院研究银行监管的教授希拉里·艾伦(Hilary Allen)表示，相对较小且关系紧密的银行储户群体加速了崩溃。
“几乎所有的储户都来自同一个社区，一个非常在线的社区，”艾伦告诉美国广播公司新闻。“如果你有像硅谷银行这样的银行，那里的绝大多数储户都在科技行业，关系非常密切，而且都在互相交谈，在这种情况下，恐慌真的会非常非常迅速地蔓延。”
平心而论，逃离该行的投资者对其财务健康状况的担忧不无道理。
硅谷银行(Silicon Valley Bank)加大了对长期美国国债和抵押贷款债券的投资，这些债券通常在低利率下提供小额但可靠的回报。然而，随着美联储在过去一年大幅提高利率，这些资产的价值大幅缩水。
2023年3月13日，美国总统乔·拜登在华盛顿特区白宫罗斯福厅谈论美国银行系统
索尔·勒布/法新社
在大额提现的前一天，硅谷银行宣布的它在出售这些不良债券上损失了18亿美元。
“这不仅仅是银行挤兑，”宾夕法尼亚大学沃顿商学院金融学教授Itamar Drechsler告诉ABC新闻。"这家银行有一个非常根本性的问题。"
Dreschler说，尽管如此，在线交流的速度和范围可能加速了银行的崩溃。
“就像一群人一起快速移动，如果它决定离开某个地方，就有问题了，”Dreschler说。“如果我们通过社交媒体和其他信息技术进行更多的协调，这可以使人群移动得更快。”
专家表示，虽然数字银行可以快速方便地取款，但这种服务的可用性可能对银行挤兑贡献很小或根本没有贡献，因为这种技术已经存在多年，没有出现重大问题。
“人们已经讨论了一段时间，数字银行的速度本身是否会导致银行挤兑，”美利坚大学的艾伦说。“我对此的看法是，相当长一段时间以来，把资金取出来一直相对容易。我不确定这有多大的不同。”
为了应对抗议和对危机蔓延的担忧，FDIC、财政部和美联储最终在周日迈出了重要一步，告诉硅谷银行的储户，FDIC将保护他们所有的资金，包括超过25万美元限额的资金。
当天晚些时候，美联储宣布了一项紧急贷款计划，以覆盖有问题的存款，并恢复对金融系统的更广泛信心。
艾伦说，网上恐慌的蔓延可能促使联邦政府决定采取如此特殊的行动，防止不确定性进一步渗入金融系统。
“这是促使拜登政府介入的担忧的一部分吗，因为它担心Twitter上非常公开的发泄也可能转移到其他银行?”她问。
周一，在白宫的一次早间讲话中，乔·拜登总统试图使消除疑虑美国人认为银行系统是健全的。
“美国人可以放心，我们的银行系统是安全的，”拜登说。“你的存款是安全的。我也向你们保证，我们不会就此止步。我们会做任何需要的事情。”
拜登当天在一次演讲中也谈到了这个问题推特帖子。
Silicon Valley Bank: How a digital bank run accelerated the collapse
ThecollapseofSilicon Valley Bank, the second-biggest bank failure in U.S. history, took place over less than 48 hours.
Customers withdrew $42 billion -- nearly a quarter of the bank's total deposits -- within a single day last week.
The speedy bank run has raised questions about the fragility of financial institutions in a digital environment marked by easy cash withdrawals and the spread of information on social media and other spaces online, where panic among a few can grow into a stampede for the exit.
Such a possibility, known as a digital bank run, heightens the risk of a sudden, widespread cash withdrawal, especially among a group of depositors who share an industry and social ties -- like the depositors in Silicon Valley Bank, experts told ABC News.
"This was the first Twitter-fueled bank run," Rep. Patrick McHenry, R-N.C., the chair of the House Financial Services Committee, said ina statementdays after the fall of Silicon Valley Bank.
The group of depositors in Silicon Valley Bank was made up of a relatively small set of venture capital firms, tech startups and other large investors.
After a woeful financial report last Wednesday set off concern, some of the depositors discussed their reactions in WhatsApp and Slack groups devoted to startups, theWall Street Journalreported.
Meanwhile, several prominent venture capitalists and other major investors voiced their concern on Twitter, amplifying fears of a collapse.
Michael Burry, an investor best known for predicting the subprime mortgage crisis, warned in anow-deleted tweet: "It is possible today we found our Enron."
On Thursday, shares of Silicon Valley Bank fell 60% in response to concern about the bank's distressed financial position.
By the early afternoon, the sudden decline of the bank took over online discussions among startup founders, according to entrepreneur Alexander Torrenegra.
"All of my chats with tech founders in the US light on fire with what's happening," Torrenegrarecountedon Twitter. "Obviously, we have a bank runoff. Surreal."
Founders Fund, a venture capital fund led by billionaire investor Peter Thiel, withdrew all of its deposits that day,Bloombergreported.
Since the bank is FDIC-insured, depositors were guaranteed protection of up to $250,000 in funds for different types of accounts held in the event of a collapse. However, many depositors in Silicon Valley Bank held accounts that far exceeded $250,000, raising the stakes for those who failed to remove their funds before a potential bank failure.
"Because information comes out faster, you get the information in real time, it's widespread and it leads people to take action," Campbell Harvey, a finance professor at Duke University, told ABC News. "If you're the first group out, you get 100% of your money and if you're the last group out, you potentially get zero."
Hilary Allen, a professor at the American University Washington College of Law who studies banking regulation, said the relatively small and tight-knit community of bank depositors helped accelerate the downfall.
"Virtually all of the depositors were from the same community and a community that was very online," Allen told ABC News. "If you've got something like Silicon Valley Bank, where the vast majority of depositors are in the tech industry and are very connected and all speaking to one another, those are the circumstances in which a panic can really flourish very, very quickly."
To be sure, investors who fled the bank held well-founded concerns about its financial health.
Silicon Valley Bank had loaded up on investments into long-term Treasury bonds and mortgage bonds, which typically deliver small but reliable returns amid low interest rates. As the Federal Reserve aggressively hiked interest rates over the past year, however, those holdings lost significant value.
A day before the major cash withdrawal, Silicon Valley Bankannouncedthat it had lost $1.8 billion on the sale of those distressed bonds.
"This isn't purely a bank run," Itamar Drechsler, a professor of finance at the University of Pennsylvania's Wharton School of Business, told ABC News. "The bank had a very fundamental problem."
Still, the speed and reach of online communication likely accelerated the bank's collapse, Dreschler said.
"Like a crowd that moves together very fast, if it decides to exit someplace, there's a problem," Dreschler said. "If we coordinate more through social media and other information technology, that can cause the crowd to move a lot faster."
While digital banking allows for quick and easy withdrawals, the availability of such a service likely contributed little or not at all to the bank run, since such technology has existed for many years without significant issue, the experts said.
"People have been talking for a while about whether the speed of digital banking itself would contribute to bank runs," said Allen, of American University. "My view on that is it has been relatively easy to get your money out for quite a while now. I'm not sure how much of a difference that has made."
In response to the outcry and fearing wider spread of the crisis, the FDIC, Treasury Department and the Fed ultimately took a major step on Sunday, telling depositors in Silicon Valley Bank that the FDIC would protect all of their funds, including those that exceed the $250,000 limit.
Later that day, the Fed announced an emergency lending program to cover the deposits at issue and restore wider confidence in the financial system.
The spread of panic online may have contributed to the federal government's decision to take such extraordinary action and prevent uncertainty from seeping further into the financial system, Allen said.
"Was that part of the concern that motivated the Biden administration to step in because it was worried that the very public venting on Twitter might transfer to other banks, as well?" she asked.
On Monday, in a morning address from the White House, President Joe Biden sought toreassureAmericans that the banking system was sound.
"Americans can rest assured that our banking system is safe," Biden said. "Your deposits are safe. Let me also assure you, we will not stop at this. We'll do whatever is needed."
Biden also addressed the issue that day in aTwitter post.
