But where in the world do investors not know about, or feel familiar with, Apple, Cisco, and Google? After all, if a French citizen wanted to learn about home country bias, she might well Google it on her iPhone. There's a reason we call these companies "multinational."
The next step, of course, is try to step through the home-bias literature to the raw data and do the breakout from scratch. But it turns out, there's a reason the home-bias literature hasn't done this yet itself: The data don't exist.
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The U.S. has several overlapping reporting regimes regarding equity ownership in U.S. companies. These include the Treasury International Capital (TIC) system used in compiling the balance of payments, reporting to the IRS in connection with the tax paid by foreign investors on U.S. company dividends, and three separate regimes administered by the SEC (reporting by "institutional investment managers" on Form 13F, by "registered management investment companies" (mutual funds) on Forms N-Q and N-CSR, and by "registered investment advisers" on Forms ADV and PF).
Several of these reporting regimes are ingeniously designed, given their objective. Some require surprisingly detailed responses. But all of them were structured for purposes other than determining the foreign ownership of the particular subclass of large U.S. multinationals. And none of them supply this information serendipitously.
Nothing should prevent large U.S. multinationals from making the "what's good for us is good for America" argument. The question is whether, in making such arguments, these companies should get priority boarding at the Capitol, or whether they should get in line with Toyota and Siemens. Certainly, the bare fact that "U.S. companies" file their corporate documents in Delaware rather than Düsseldorf shouldn't matter. And if we've been waving them up to the gate on the assumption that their owners are largely American, we might want to take a closer look at their boarding passes.
Chris William Sanchirico is a professor of law, business, and public policy at the University of Pennsylvania Law School and the Wharton School. He is also a faculty affiliate of the Penn Wharton Public Policy Initiative. Follow Penn Wharton PPI on Twitter