What is a paper filed exhibit? See also, how do you find an exhibit when the hyperlink is not required pursuant to Rule 105 of Regulation S-T? And also, are there exhibits missing from EDGAR?!

A paper "(P)" filed exhibit is like any other, except that it was submitted to the SEC before the EDGAR electronic filing system was implemented in 1996. So, unfortunately, paper filed exhibits are not available on EDGAR. The SEC provides a special webform to submit Freedom of Information Act (FOIA) requests for "Exhibits to public filings" under "Type of document", however, if the exhibit you are seeking was originally filed before 1985, the SEC FOIA office will likely direct you to the National Archives in College Park.

Out of the tens of thousands of exhibits referenced by S&P 500 companies in 2019 only 538 were paper filed. However, 1 in 4 S&P 500 companies reference at least one paper filed exhibit. Those 538 paper filed exhibits are comprised primarily of energy company exhibit 4 indentures, some dating back to the 1930s. Just 188 of the 538 paper exhibits in 2019 are exhibit-10 material contracts. A couple high profile exhibit-10 paper filed exhibits are:

Billionaire Samuel Zell's 1993 Noncompete Agreement with Equity Residential
Hershey Company's 1980 License Agreement for KitKat and Rolo

Fun Facts;

Duke Energy currently references 86 paper exhibits, the most out of any SEC reporting company as of 2019 10-Ks (all of them exhibit 4 indentures and supplements).
The oldest Exhibit 10 referenced in a 2019 10-K pre-dates the SEC itself, a 1927 Water Supply Contract between Cal Water and PG&E.

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