Authorization for the Export-Import Bank expires Sept. 30, and Congress must decide whether to renew the charter of the taxpayer-funded outfit. Proponents claim that “Ex-Im” is needed to fill gaps in private financing, which might sound plausible if not for the roster of monster corporations that pocket most of the subsidies. That list includes:

• Boeing, the world’s largest aerospace company, with a market cap exceeding $91 billion.

• General Electric, the appliance and lighting conglomerate, valued at $267 billion.

• Dow Chemical Co., the materials and chemicals producer, with 2013 sales of $57 billion.

• Bechtel, the engineering and construction transnational, ranked by Forbes as the fourth-largest privately held company (by revenue).

• Caterpillar, global purveyor of mining and construction equipment, with 2013 sales and revenues of $55 billion.

• John Deere, the king of tractors and dump trucks, ranked 97th on the Forbes 500.

The major beneficiary countries include the likes of China, Russia and Venezuela, nations to which Ex-Im doles out loans and loan guarantees as well as capital and credit, compliments of U.S. taxpayers who are on the hook for any and all losses.

Bank officials insist that they carefully manage the financial risks (despite hundreds of millions of dollars in losses throughout the 1980s). Nor does the latest report to Congress by ExIm’s inspector general inspire confidence. It notes that Ex-Im has insufficient policies to prevent waste, fraud and abuse. In another review, the Government Accountability Office reported that the bank appears to be using inappropriate risk modeling that could produce inaccurate estimates of both subsidy costs and potential losses.

The risk to taxpayers grows as the value of bank transactions increases — to $27.3 billion in FY 2013 alone, up 28 percent from four years earlier. Taxpayer exposure now totals $134 billion. However, the inspector general suggests that the bank’s sloppy record-keeping obscures the actual amount of outstanding commitments, which likely exceed the $140 billion cap set by Congress in 2012.

But with strong growth in privately financed exports, there is simply no justification for maintaining this conduit of corporate welfare. A mere 2 percent or so of all U.S. exports receive ExIm financing. In other words, 98 percent of American exporters are competing just fine without the bank’s intervention. Terminating Ex-Im’s charter should thus be an easy call for lawmakers.

Bank advocates offer myriad excuses for maintaining government financing, including the need to bankroll deals that supposedly pose too much political or economic risk to garner private capital. But such justifications do not stand up to the facts, as is obvious from bank deals with many of the world’s most successful companies.

In decades past, political and economic turmoil did present export risks, but global trade is now firmly entrenched. If the bank were stepping in where private investors fear to tread, a larger proportion of its financing would be directed to Africa and Latin America, where risks are greatest. Instead, bank authorizations last year were concentrated in Asia ($9.7 billion), followed by Europe ($5.7 billion) and North America ($3.4 billion). In contrast, Latin America has received $2.9 billion and Africa a measly $600 million.

To the extent ExIm does finance deals that the private sector supposedly snubs, taxpayers are justified in questioning whether they should be saddled with risk that private investors deem unacceptable.

Rather than recommit to the government’s risky and inefficient finance scheme, lawmakers should focus on reducing tax and regulatory barriers to exports. For example, private banks and investors are drowning in DoddFrank regulations, while the costs of Obamacare weigh particularly heavily on smaller firms. In fact, regulatory costs have increased by nearly $73 billion a year under the Obama Administration.

Congress must decide by summer’s end whether to extend billions of dollars in corporate welfare on the backs of taxpayers or allow private investors to finance U.S. exports — as it does for the vast majority of them. Policymaking could not get any easier.

 - Diane Katz is a research fellow in regulatory policy at the Heritage Foundation’s Roe Institute for Economic Studies.