Charles and David Koch have sued the Cato Institute, Kathryn Washburn, the widow of William Niskanen, former President of Cato, and a Director herself and Edward Crane, a shareholder and current President of Cato, essentially for control of the Institute.
Before reaching for the popcorn, a bit of history is useful, which is provided at Politico and in the complaint. Cato was originally founded in Kansas as the Charles Koch Foundation by Charles Koch, George Pearson, Roger MacBride, Murray Rothbard and Ed Crane. Rothbard left, Pearson sold his shares back and who knows (RTFR) what happened to MacBride, but David Koch and William Niskanen joined. Each of the partners has an equal number of shares and there are agreements, which on the face say that if anyone leaves the Institute or the mortal coil, the shares have to be offered back. Before Nishkanen's death there were four shareholders, Crane, Niskanen and the two Kochs.
Crane and widow Washburn claim (read infra) that the shares were offered back and refused, therefore they pass by Niskanen's will to Washburn, the Institute and the Institute for Justice in equal shares (see the will, Politico appears to have gotten this wrong). That leaves control of Cato well up in the air. Eli hopes for a washing of laundry.