American billionaire and co-founder of Microsoft Bill Gates has sold a large stake of his shares in a British firm that does business with Israel's prison system and military, the Telegraph reported Friday. 

G4S, an international company worth tens of billions of dollars employing over 600,000 employees worldwide, provides security systems to Israeli prisons and checkpoints in the West Bank. 

According to the Israeli NGO Who Profits, in 2007 G4S signed a contract with the Israel Prison Service to provide surveillance systems to Israeli prisons, including Ofer, Ketziot and Megiddo, where Palestinian detainees are held as political prisoners without trial.  Addameer, a Palestinian NGO advocating for the human rights of Palestinian prisoners, issued a call to action in April along with dozens of other Palestinian and international organizations urging Gates to divest from G4S.

Gates, considered the world's richest man, held a 3 percent stake in the company through his philanthropic Bill & Melinda Gates Foundation and private investment Cascade, estimated to be worth $167 million.  It is unclear how many shares he still holds. 

Addameer and other supporters of the Boycott, Divestment and Sanctions Movement issued a statement Friday expressing satisfaction with the move:

“We are glad the pressure on the Gates Foundation to divest from G4S is starting to work.  We urge the Foundation to sell any remaining shares it still holds and release a public statement pledging not to invest in corporations profiting from Israel’s military occupation,” said Rafeef Ziadah, Senior Campaigns Officer at War on Want. 

War on Want partner, Addameer Palestinian Prisoner and Human Rights Association added, 'we have been arguing that it is completely unacceptable for a charitable foundation to be investing in a company, like G4S, which participates in gross human rights violations against Palestinian political prisoners, including child prisoners.  We welcome this step in the right direction.'” 

Israel hospitalized 40 hunger-striking Palestinian detainees this week as their fast entered a second month, the spokeswoman of Israel's Prison Authority said Tuesday.  In all, some 240 detainees are currently on a hunger strike. 

In 2012, several Palestinian detainees went on hunger strike to protest their arrests or administrative detention without trial or indictment; some to the point that their lives were in danger.  The hunger strikes of that year garnered a great deal of public and media attention, as well as negativity toward Israeli political leaders and prison officials.