Three employees with knowledge of the situation say that the employees who helped write and distribute the open letter have been fired.
The letter was written by some employees of the company. The company was asked to rein in the billionaire because of his public behavior and use of social media. Mr. Musk is close to closing a deal to buy the social networking site.
Some of the letter's organizers were fired by the company, according to an email from the president and COO. In her email, obtained by The New York Times, she said the company had investigated and fired a number of employees.
The letter, solicitations and general process made employees feel uncomfortable, intimidated and angry because the letter pressured them to sign onto something that did not reflect their views. We have too much important work to be doing overreaching activism.
It wasn't clear how many employees were let go. The spokesman for the company did not return a request for comment.
The open letter was written by Mr. Musk in response to recent accusations of sexual harassment. Mr. Musk spoke to employees via video call on Thursday to answer their questions.
Insider reported in May that Mr. Musk propositioned a flight attendant for sex on a flight to London. According to the article, the details of which were not independently verified by The Times, the flight attendant claimed that he exposed himself to her and offered her a horse.
Mr. Musk made fun of horses and his genitalia on the social networking site. The sexual harassment allegations against Mr. Musk were false according to Ms. Shotwell.
Three employees said that Mr. Musk is rarely challenged by his own workers. He told the company's workers that they had to spend at least 40 hours in the office or face dismissal.
The open letter asked that the leaders of the company condemn and respond to all forms of unacceptable behavior.
In her email to staff, Ms. Shotwell wrote, "Blanketing thousands of people across the company with repeated emails and asking them to sign letters and fill out surveys is not acceptable."
She told them to use their time to do their best work. This is how we will travel to Mars.