Two early investors in Uber said their efforts to change the company's "aggressive" culture from within haven't worked, and thus are going public in the the hope that others can exert additional pressure on the company.

The two investors, Mitch and Freda Kapor of Kapor Capital, wrote an open letter to the Uber board and investors published on Medium Thursday.



"We feel we have hit a dead end in trying to influence the company quietly from the inside," the two said in the letter. The Kapors decried "toxic patterns" they have observed at Uber, and noted that past promises to improve behavior ultimately returned to "aggressive business as usual."