Zuckerberg placed a statement on his Facebook wall on December 9 , 2015 which said that he wants " to add my voice in support of Muslims in our community and around the world " in response to the aftermath of the November 2015 Paris attacks and the 2015 San Bernardino attack . The statement also said that Muslims are " always welcome " on Facebook , and that his position was a result of the fact that " as a Jew , my parents taught me that we must stand up against attacks on all communities . " On February 24 , 2016 , Zuckerberg sent out a company-wide internal memo to employees formally rebuking employees who had crossed out handwritten " Black Lives Matter " phrases on the company walls and had written " All Lives Matter " in their place . Facebook allows employees to free-write thoughts and phrases on company walls . The memo was then leaked by several employees . As Zuckerberg had previously condemned this practice at previous company meetings , and other similar requests had been issued by other leaders at Facebook , Zuckerberg wrote in the memo that he would now consider this overwriting practice not only disrespectful , but " malicious as well . " According to Zuckerberg 's memo , " '' Black Lives Matter '' does n't mean other lives do n't -- it 's simply asking that the black community also achieves the justice they deserve . " The memo also noted that the act of crossing something out in itself , " means silencing speech , or that one person 's speech is more important than another 's . " Zuckerberg also said in the memo that he would be launching investigations into the incidents . New York 's '' Daily News '' interviewed Facebook employees who commented anonymously that , " Zuckerberg was genuinely angry about the incident and it really encouraged staff that Zuckerberg showed a clear understanding of why the phrase ' Black Lives Matter ' must exist , as well as why writing through it is a form of harassment and erasure . " In January 2017 , Zuckerberg criticized Donald Trump 's executive order to severely limit immigrants and refugees from some countries
2015 San Bernardino attack
2015 San Bernardino attack
Mark Zuckerberg