SAN FRANCISCO — Two Google employees, Claire Stapleton and Meredith Whittaker, helped organize a 20,000-person walkout from the company last November. Now they say they have paid a price for their actions.

In a letter shared internally with co-workers on Monday and reviewed by The New York Times, Ms. Stapleton, a marketing manager at YouTube, said Google had demoted her after she urged colleagues to walk out from the company last year over its treatment of sexual harassment. Ms. Whittaker, an artificial intelligence researcher, said in the letter that she had also been “informed my role would be changed dramatically.”

In addition to the demotion, Ms. Stapleton said, Google instructed her to take medical leave even though she was not sick, according to the letter. And Ms. Whittaker said she had been told to abandon her external work at New York University, where she runs research on artificial intelligence and ethics for the university’s A.I. Now Institute.

Ms. Stapleton said she had hired a lawyer and reversed the demotion. Ms. Whittaker did not address whether her role had ultimately changed.