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Views of investors and executives
American investor Warren Buffett warned investors about bitcoin in 2014, "Stay away from it. It's a mirage, basically." He repeated the warning in 2018 calling bitcoin "probably rat poison squared". He believes that bitcoin is a non-productive asset. "When you're buying nonproductive assets, all you're counting on is the next person is going to pay you more because they're even more excited about another next person coming along."

Buffett's close associate Charlie Munger is even more direct in his disdain. Trading cryptocurrencies is "just dementia" according to Munger. Bitcoin is "worthless" and a "turd".

John Bogle, the founder of The Vanguard Group, is also very direct "Avoid bitcoin like the plague. Did I make myself clear? .... There is nothing to support bitcoin except the hope that you will sell it to someone for more than you paid for it."

George Soros, answering an audience question after a speech in Davos, Switzerland in 2018, said that cryptocurrencies are not a store of value but are an economic bubble. Nevertheless, they may not crash due to the rising influence of dictators trying to "build a nest egg abroad".

James Chanos, known as the "dean of the short sellers", believes that bitcoin and other cryptocurrencies are a mania and useful only for tax avoidance or otherwise hiding income from the government. Bitcoin "is simply a security speculation game masquerading as a technological breakthrough in monetary policy".

Two lead software developers of bitcoin, Gavin Andresen and Mike Hearn, have warned that bubbles may occur.

On 13 September 2017, Jamie Dimon referred to bitcoin to as a "fraud", comparing it to pyramid schemes, and stated that JPMorgan Chase would fire employees trading while the company released a report critical of the cryptocurrency. However, in a January 2018 interview Jamie Dimon voiced regrets about his earlier bitcoin remarks, and noted "The blockchain is real, You can have cryptodollars in yen and stuff like that. ICOs ... you got to look at everyone individually."

Alibaba chairman Jack Ma stated in 2018, "There is no bubble for blockchain, but there's a bitcoin bubble" and "[blockchain] technology itself isn’t the bubble, but bitcoin likely is".

Fraud concerns
Some journalists, economists, and the central bank of Estonia have voiced concerns that bitcoin is a Ponzi scheme. In 2013, Eric Posner, a law professor at the University of Chicago, stated that "a real Ponzi scheme takes fraud; bitcoin, by contrast, seems more like a collective delusion." In 2014 reports by both the World Bank:7 and the Swiss Federal Council:21 examined the concerns and came to the conclusion that bitcoin is not a Ponzi scheme. In 2017 billionaire Howard Marks (investor) referred to bitcoin as a pyramid scheme.

On 12 September 2017, Jamie Dimon, CEO of JP Morgan Chase, called bitcoin a "fraud" and said he would fire anyone in his firm caught trading it. Zero Hedge claimed that the same day Dimon made his statement, JP Morgan also purchased a large amount of bitcoins for its clients.

Value forecasts
Financial journalists and analysts, economists, and investors have attempted to predict the possible future value of bitcoin. In April 2013, economist John Quiggin stated, "bitcoins will attain their true value of zero sooner or later, but it is impossible to say when". A similar forecast was made in November 2014 by economist Kevin Dowd.

In December 2013, finance professor Mark T. Williams forecast that bitcoin would trade for less than $10 by mid-year 2014. In the indicated period bitcoin has exchanged as low as $344 (April 2014) and during July 2014 the bitcoin low was $609. In December 2014, Williams said, "The probability of success is low, but if it does hit, the reward will be very large."

In November 2014, David Yermack, Professor of Finance at New York University Stern School of Business, forecast that in November 2015 bitcoin may be all but worthless. In the indicated period bitcoin has exchanged as low as $176.50 (January 2015) and during November 2015 the bitcoin low was $309.90.

In May 2013, Bank of America FX and Rate Strategist David Woo forecast a maximum fair value per bitcoin of $1,300. Bitcoin investor Cameron Winklevoss stated in December 2013 that the "small bull case scenario for bitcoin is... 40,000 USD a coin".

Obituaries
The "death" of bitcoin has been proclaimed numerous times. One journalist has recorded 29 such "obituaries" as of early 2015.

Forbes magazine declared bitcoin "dead" in June 2011, followed by Gizmodo Australia in August 2011. Wired magazine wrote it had "expired" in December 2012. Ouishare Magazine declared, "game over, bitcoin" in May 2013, and New York Magazine stated bitcoin was "on its path to grave" in June 2013. Reuters published an "obituary" for bitcoin in January 2014. Street Insider declared bitcoin "dead" in February 2014, followed by The Weekly Standard in March 2014, Salon in March 2014, Vice News in March 2014, and Financial Times in September 2014. In January 2015, USA Today stated bitcoin was "headed to the ash heap", and The Telegraph declared "the end of bitcoin experiment". In January 2016, former bitcoin developer Mike Hearn called bitcoin a "failed project".

Peter Greenhill, Director of E-Business Development for the Isle of Man, commenting on the obituaries paraphrased Mark Twain saying "reports of bitcoin's death have been greatly exaggerated".

Reception
Some economists have responded positively to bitcoin while others have expressed skepticism. François R. Velde, Senior Economist at the Chicago Fed, described it as "an elegant solution to the problem of creating a digital currency". Paul Krugman and Brad DeLong have found fault with bitcoin, questioning why it should act as a reasonably stable store of value or whether there is a floor on its value. Economist John Quiggin has criticized bitcoin as "the final refutation of the efficient-market hypothesis".

David Andolfatto, Vice President at the Federal Reserve Bank of St. Louis, stated that bitcoin is a threat to the establishment, which he argues is a good thing for the Federal Reserve System and other central banks, because it prompts these institutions to operate sound policies.:33

Free software movement activist Richard Stallman has criticized the lack of anonymity and called for reformed development. PayPal President David A. Marcus calls bitcoin a "great place to put assets" but claims it will not be a currency until price volatility is reduced. Bill Gates, in relation to the cost of moving money from place to place in an interview for Bloomberg L.P. stated: "Bitcoin is exciting because it shows how cheap it can be."

In November 2013, three US government officials testified at senate hearings that "Bitcoin has legitimate uses". According to the Washington Post, "Most of the other witnesses echoed those sentiments."

Acceptance by merchants
Most bitcoin transactions take place on a cryptocurrency exchange, rather than being used in transactions with merchants. Delays processing payments through the blockchain of about ten minutes make bitcoin use very difficult in a retail setting. Prices are not usually quoted in units of bitcoin and many trades involve one, or sometimes two, conversions into conventional currencies. Merchants that do accept bitcoin payments may use payment service providers to perform the conversions.

In 2017 and 2018 bitcoin's acceptance among major online retailers included only three of the top 500 U.S. online merchants, down from five in 2016. Reasons for this decline include high transaction fees due to bitcoin's scalability issues and long transaction times.

Bloomberg reported that the largest 17 crypto merchant-processing services handled $69 million in June 2018, down from $411 million in September 2017. Bitcoin is "not actually usable" for retail transactions because of high costs and the inability to process chargebacks, according to Nicholas Weaver, a researcher quoted by Bloomberg. High price volatility and transaction fees make paying for small retail purchases with bitcoin impractical, according to economist Kim Grauer.
Bitcoin started to be accepted also for real estate payments in late 2017. The first recorded sale of a house in exchange for bitcoin happened in September 2017, when Texas based Kuper Sotheby's International Realty brokered the deal using bitpay.com to process the payment.

Two months later, a first recorded sale of apartment in the world and first real estate property in Europe was sold for bitcoin in November 2017 in the Czech republic. The Czech real estate agency HOME Hunters brokered a deal of a 3-room apartment for a Russian buyer without using a payment service providers at all.

Some U.S. political candidates, including New York City Democratic Congressional candidate Jeff Kurzon have said they would accept campaign donations in bitcoin.

Payment service providers
Merchants accepting bitcoin, such as Dish Network, use the services of bitcoin payment service providers such as BitPay or Coinbase. When a customer pays in bitcoin, the payment service provider accepts the bitcoin on behalf of the merchant, directly converts it, and sends the obtained amount to merchant's bank account, charging a fee of less than 1 percent for the service.

Use in retail transactions
Due to the design of bitcoin, all retail figures are only estimates. According to Tim Swanson, head of business development at a Hong Kong-based cryptocurrency technology company, in 2014, daily retail purchases made with bitcoin were worth about $2.3 million. MIT Technology review estimates that, as of February 2015, fewer than 5,000 bitcoins per day (worth roughly $1.2 million at the time) were being used for retail transactions, and concludes that in 2014 "it appears there has been very little if any increase in retail purchases using bitcoin."

Financial institutions
Bitcoin companies have had difficulty opening traditional bank accounts because lenders have been leery of bitcoin's links to illicit activity. According to Antonio Gallippi, a co-founder of BitPay, "banks are scared to deal with bitcoin companies, even if they really want to". In 2014, the National Australia Bank closed accounts of businesses with ties to bitcoin, and HSBC refused to serve a hedge fund with links to bitcoin. Australian banks in general have been reported as closing down bank accounts of operators of businesses involving the currency; this has become the subject of an investigation by the Australian Competition and Consumer Commission. Nonetheless, Australian banks have adopted the blockchain technology on which bitcoin is based.

In September 2019 the Central Bank of Venezuela, at the request of PDVSA, ran tests to determine if bitcoin and Ethereum could be held in central bank's reserves. The request was motivated by oil company's goal to pay its suppliers.

As an investment
Some Argentinians have bought bitcoins to protect their savings against high inflation or the possibility that governments could confiscate savings accounts. During the 2012–2013 Cypriot financial crisis, bitcoin purchases in Cyprus rose due to fears that savings accounts would be confiscated or taxed.

Other methods of investment are bitcoin funds. The first regulated bitcoin fund was established in Jersey in July 2014 and approved by the Jersey Financial Services Commission. Also, c. 2012 an attempt was made by Cameron and Tyler Winklevoss (who in April 2013 claimed they owned nearly 1% of all bitcoins in existence) to establish a bitcoin ETF. As of 10 March 2017 the bitcoin ETF was declined by the SEC because of regulatory concerns. The price fell 15% in a few minutes, but soon mostly recovered. As of early 2015, they have announced plans to launch a New York-based bitcoin exchange named Gemini, which has received approval to launch on 5 October 2015. On 4 May 2015, Bitcoin Investment Trust started trading on the OTCQX market as GBTC. Forbes started publishing arguments in favor of investing in December 2015. In 2013 and 2014, the European Banking Authority and the Financial Industry Regulatory Authority (FINRA), a United States self-regulatory organization, warned that investing in bitcoins carries significant risks. Forbes named bitcoin the best investment of 2013. In 2014, Bloomberg named bitcoin one of its worst investments of the year. In 2015, bitcoin topped Bloomberg's currency tables.

To improve access to price information and increase transparency, on 30 April 2014 Bloomberg LP announced plans to list prices from bitcoin companies Kraken and Coinbase on its 320,000 subscription financial data terminals. In May 2015, Intercontinental Exchange Inc., parent company of the New York Stock Exchange, announced a bitcoin index initially based on data from Coinbase transactions.

According to Bloomberg, in 2013 there were about 250 bitcoin wallets with more than $1 million worth of bitcoins. The number of bitcoin millionaires is uncertain as people can have more than one wallet.

Venture capital
Venture capitalists, such as Peter Thiel's Founders Fund, which invested US$3 million in BitPay, do not purchase bitcoins themselves, instead funding bitcoin infrastructure like companies that provide payment systems to merchants, exchanges, wallet services, etc. In 2012, an incubator for bitcoin-focused start-ups was founded by Adam D*****r, with financing help from his father, venture capitalist Tim D*****r, one of the largest bitcoin holders after winning an auction of 30,000 bitcoins, at the time called 'mystery buyer'. The company's goal is to fund 100 bitcoin businesses within 2–3 years with $10,000 to $20,000 for a 6% stake. Investors also invest in bitcoin mining. According to a 2015 study by Paolo Tasca, bitcoin startups raised almost $1 billion in three years (Q1 2012 – Q1 2015).

Crowdfunding
Bitcoin is useful for crowdfunding. For example, one college football sign netted over $20,000 in donations for a bitcoin enthusiast. He was shown by local TV company with a broadsheet "Hi mom, send bitcoins".

Political economy
The decentralization of money offered by virtual currencies like bitcoin has its theoretical roots in the Austrian school of economics, especially with Friedrich von Hayek in his book Denationalisation of Money: The Argument Refined, in which he advocates a complete free market in the production, distribution and management of money to end the monopoly of central banks.

Bitcoin appeals to tech-savvy libertarians, because it so far exists outside the institutional banking system and the control of governments. However, researchers looking to uncover the reasons for interest in bitcoin did not find evidence in Google search data that this was linked to libertarianism.

Bitcoin's appeal reaches from left wing critics, "who perceive the state and banking sector as representing the same elite interests, recognising in it the potential for collective direct democratic governance of currency" and socialists proposing their "own states, complete with currencies", to right wing critics suspicious of big government, at a time when activities within the regulated banking system were responsible for the severity of the financial crisis of 2007–08, "because governments are not fully living up to the responsibility that comes with state-sponsored money". Bitcoin has been described as "remov the imbalance between the big boys of finance and the disenfranchised little man, potentially allowing early adopters to negotiate favourable rates on exchanges and transfers – something that only the very biggest firms have traditionally enjoyed". Two WSJ journalists describe bitcoin in their book as "about freeing people from the tyranny of centralised trust".