Chief Justice John Roberts Dumps Microsoft Stock by Barb Darrow @FortuneMagazine February 5, 2016, 10:11 AM EDT E-mail Tweet Facebook Linkedin Share icons U.S. Supreme Court Chief Justice John Roberts has sold off somewhere between $250,000 and $500,000 worth of Microsoft msft stock in before the court is slated to hear a case involving the software giant, according to the Associated Press. Federal judges are supposed to recuse themselves from cases involving companies they have an interest in and, but there are lapses. In October Chief Justice Roberts took part in a deposition involving Texas Instruments TXN . But financial disclosure forms from the previous year showed that he or a family member owned shares in the company. When the issue was raised, the court’s spokeswoman attributed the issue to human error. For more on the Supreme Court These incidents have caused some organizations, including grassroots watchdog “Fix the Court,” to call for court reform to eliminate conflicts and increase transparency. Last week, the Supreme Court said it would take on a case about whether a class action suit alleging defects in Microsoft’s Xbox gaming console can go forward. Get Data Sheet, Fortune’s daily newsletter about the business of technology. Fortune reached out to the Supreme Court’s spokeswoman for comment and will update this story as needed. In October there was a kerfuffle when Justice Stephen Breyer sat on a case involving Johnson Controls JCI , despite his wife’s ownership of shares that company. She ended up selling those shares. Justice Samuel Alito, who also owned shares in that company, sat out the case, according to the AP report which also noted that three of the nine justices, Roberts, Alito and Breyer, own individual stocks.