Democratic presidential hopeful Massachusetts Senator Elizabeth Warren gestures as she arrives for a town hall devoted to LGBTQ issues hosted by CNN and the Human rights Campaign Foundation at The Novo in Los Angeles on October 10, 2019. ROBYN BECK | AFP | Getty Images

Presidential hopeful Sen. Elizabeth Warren is drafting a sweeping piece of legislation that would go far beyond breaking and blocking deals between companies and would exert more control over some of America's largest firms. People with knowledge of the bill and who support it say the measure takes important steps towards clarifying the rule book under which the country's largest companies play, after years of lax or incomplete oversight. Its detractors, including academics and antitrust lawyers who spoke with CNBC on the condition of anonymity, say it takes unprecedented steps to legislate America's largest companies that undoes decades of jurisprudence and weakens the country's competitive stance. The bill, tentatively named the Anti-Monopoly and Competition Restoration Act, is coauthored with Rep. David Cicilline, D-R.I., who chairs the antitrust subcommittee on the House Judiciary panel. Cicilline has said he will not introduce new antitrust legislation until the investigations he is leading into the growing power of big tech companies like Facebook have concluded. Bloomberg News first reported on the anti-merger aspects of the bill. CNBC has reviewed a draft of the bill. The legislation ultimately proposed may take a different shape. But its ideas demonstrate how dramatically Warren wishes to approach antitrust policy in the U.S. Warren, who has built her top-tier Democratic presidential campaign on a populist call for structural change in the American economy, has already pushed for breaking up big technology companies like Amazon and Facebook. The proposed antitrust legislation goes far beyond regulating merger-and-acquisition activity and ending megamergers. It outlines a set of provisions to apply to any company with "market power." The line Warren draws for such companies is far below the standard set for monopolistic companies, which hold 70% market share. The draft bill would instead focus on any companies with buying power, which could include corporations with market share as low as 25%. It would also focus on all companies with more than $40 billion in sales. The guidelines cover everything from the way these companies treat their competitors to how they price their products. Spokespeople for Warren and Cicilline declined to comment. The guidelines mimic similar ones laid out in Europe, which has taken a more aggressive approach to antitrust than the U.S. with its "abuse of dominance standard." Critics of Europe's approach argue there is a reason that the world's most innovative companies, like Google, have been born in Silicon Valley and not Paris or Berlin. Its defenders argue concerns over the potential ability of companies like Amazon and Facebook to abuse their power overrides concerns of economic power. "Over the last 3 decades, powerful corporations have amassed too much power over the United States economy, stifling competition in United States markets and harming consumers, workers, small businesses and entrepreneurs, and innovation," the bill's authors write.

Undoing Supreme Court rulings

A key part of the bill prohibits dominant companies from "denying access to essential facilities." That language flies directly in the face of an influential Supreme Court case, Verizon v. Trinko. That 2004 ruling protects companies from lawsuits if they do not allow their competitors access to infrastructure deemed necessary for business. Broadly speaking, such infrastructure could be access to anything from a bridge to a search engine. The Trinko case stemmed from a lawsuit against Verizon for not providing competitors access to the telephone network it had built up. With that Supreme Court blessing, dominant companies have largely been free of the threat of litigation to give certain access to competitors. But Warren's draft bill would codify into law what the Supreme Court has declined to impose punishment on. "This (proposed regulation) would essentially change the presumption that a refusal to share facilities - which is now presumptively lawful - to nearly conclusively unlawful," said Professor John Lopatka, an antitrust scholar at Penn State Law. If enacted, the measure could have broad repercussions, including on companies like Amazon and Facebook that deal with the flow of data, an increasingly important tool in today's economy. Facebook was accused by the U.K. Parliament last year of cutting off access to its data to Twitter's Vine social video app, impairing its competitor in the process. The idea of monitoring the flow of information as anti-competitive behavior has been echoed elsewhere, and on a bipartisan basis. Republican Makan Delrahim, whom Trump appointed the head of the Justice Department's antitrust division, recently said in a speech the DOJ plans to be "especially vigilant about the potential for anti-competitive effects when a company cuts off a profitable relationship supplying business partners with key data, code, or other technological inputs in ways that are contrary to the company's economic interests." Others, though, say such stipulations in the draft bill would force companies to give up the rewards of their own investment and ideas by passing them on to others. "The essence of Trinko was we want to create an incentive for firms to create these facilities to innovate and come up with this infrastructure. If you require a firm that succeeds to share that infrastructure with its rivals, the firm has less of an incentive to make those investments," said Professor Lopatka. The bill would also place limits on the ability of any company with market power to engage in predatory pricing. Predatory pricing – the act of undercutting a rival with prices so low that they go out of business – is rarely litigated because it is nearly impossible to prove if it is not shown that a company will be successful in its efforts. According to the bill, though, it wouldn't matter if a company's efforts to undercut its rivals are likely to succeed. It would only matter whether a company prices its products for less than it costs to make them. Using low costs to hammer out competition is a tool that is frequently employed by larger companies like Walmart. Toys R Us blamed the big-box retailer in part for its liquidation by claiming the big box retailer slashed its toy prices so low it could not compete. Lawyers and academics who oppose the bill say the language will hurt consumers rather than helping them by limiting the ability of companies to pass on cost-savings they get through efficiencies of scale. It may also make it harder for new entrants to take on giants like Amazon, they say. The bill recommends a number of punishments for executives at companies who knowingly defy it, including fines and jail time. The Sherman Act, a federal statute that outlaws monopolistic business behavior, does allow the government to prosecute CEOs who lead allegedly anti-competitive companies. But such prosecutions are rare, and are reserved for CEOs engaged directly in an activity that limits competition, like price-fixing.

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