Talks over whether Amazon is in breach of government antitrust laws which enforce fair markets have begun on Capitol Hill in light of the online retail giant's recent wave of success, investors claim.

After a period of monumental success which saw its individual stock price soar to above $1,000 and includes its $13.7billion takeover of WholeFoods and Prime Day, its most profitable day on record, there are rumors the company is on the radar of market watchdogs who fear it may be becoming too big.

Douglas Kass, the president of Seabreeze Partners Management Inc. and former senior portfolio manager at Omega Advisors, said on Wednesday that discussions are in early stages at Capitol Hill.

Amazon CEO Jeff Bezos was unperturbed by fears surrounding his growing empire on Thursday as he arrived at the Sun Valley Conference in Idaho

He encouraged investors to start shorting the company, claiming a sudden slump in stock prices is inevitable in light of the apparently looming government scrutiny.

'I am shorting Amazon today because I have learned that there are currently early discussions and due diligence being considered in the legislative chambers in Washington, D.C., with regard to possible antitrust opposition to Amazon's business practices, pricing strategy and expansion announcements already made (as well as being aimed at expansion strategies being considered in the future).

'If I am correct, word of this could lower Amazon's shares by 10% overnight.

'And if expansion or pricing prohibitions are attacked for antitrust reasons (or for other reasons), a far more severe market impact is possible,' wrote Kass in his column for Real Money on The Street.

Neither the Federal Trade Commission, the Subcommittee of Antitrust Law or Amazon has commented on the rumors.

Amazon's stock price grew to $1,000 in June from $1 when it began in 1997 and $300 in 2015

The company announced in June that it was acquiring Whole Foods for $13.7billion - finally establishing its bricks-and-mortar presence

The company and its CEO Jeff Bezos have been on the president's radar since before he was sworn in. Part of Trump's distaste for Bezos is the newspaper which he owns - The Washington Post.

The billionaire is among the president's many Twitter targets and has been berated by him in the past.

He has already floated the idea of prosecuting Bezos for antitrust breaches.

In a 2016 interview with Sean Hannity, he said: 'Bezos believes I would go after him for antitrust because he has a huge antitrust problem.'

The problem, he said, was that in his acquisition of the Washington Post, Bezos had assigned teams of journalists to pour over every aspect of the president's life to find dirt on him.

Amazon declined to comment.

On Wednesday, market insiders said talks had begun in the nation's capital about looking in to whether Amazon was in breach of antitrust laws

WHAT ARE THE ANTITRUST LAWS AND HOW DO THEY AFFECT AMAZON? There are three antitrust laws which are enforced both by the Federal Trade Commission and the United States Department of Justice. There is also a United States House Judiciary Subcommittee on Regulatory Reform, Commercial and Antitrust Law. The laws - the earliest of which dates back to 1890 - were created to enforce fair trading and keep the markets reasonable. Their focus is on keeping prices low and quality high. In essence, they were designed to protect consumers. They are The Sherman Act, the The Federal Trade Commission Act and The Clayton Act. Because of this, how exactly they relate to concerns over Amazon's growing empire is not clear. Amazon serves customers well but, because of its dominance across so many industries, it is a problem for other businesses. The Sherman Act deals with monopoly laws and is most likely the law which would apply to concerns about Amazon. Monopolies are illegal if one firm controls the market and has obtained its position by non-competitively crushing other businesses. The argument for whether Amazon is in breach of any of the laws lies in if it has achieved its position through what the Department of Justice defines calls 'anti-competitive conduct'. Under the FTC guidelines, 'it is unlawful for a company to monopolize or attempt to monopolize trade, meaning a firm with market power cannot act to maintain or acquire a dominant position by excluding competitors or preventing new entry.' The FTC's refers to 'unreasonable methods' but does not specify what those unreasonable methods are. Advertisement

The president has long held the company and its CEO in disdain. He regularly tweets his disapproval for Bezos and his newspaper, The Washington Post

'We can't let him get away with it. Every hour we're getting calls from reporters from the Washington Post asking ridiculous questions,' he said, adding that the stories were 'bad' and 'wrong'.

Wall Street expert Douglas Kass said he was prepared to start betting on an Amazon slump

Trump also claimed that the only reason Bezos bought the newspaper was to try to use it to sling mud at politicians and avoid paying business taxes.

There was no suggestion on Wednesday whether the rumored antitrust talks were being led by Democrats or Republicans.

Amazon's growth had been gradual since its foundation 20 years ago until 2015 when it suddenly embarked on a sharp spike.

In the past two years, its stock price has grown from around $300 in January 2015 to $808 in January 2017. It has climbed even more in the last six months and reached $1,006 in June.

Along with the rise came Bezos's acquisition of the Washington Post and his bombshell WholeFoods announcement on June 16.

The company already dominates in the online retailer, book and cloud space industries. The WholeFoods takeover pushes it into the realms of not only groceries but it establishes its bricks and mortar presence.

It has also launched its bid in the entertainment space with Fire, its unique TV service, and Amazon Video, its buy or rent movie service.

Amazon.com Inc. also owns a number of other big internet and business names including IMDB, the online movie information database and Alexa.com, a data-gathering company which provides analytics.

Amazon have declined to comment.