What they're saying:

• Senate Commerce Committee leaders John Thune (R) and Bill Nelson (D) sent Facebook CEO Mark Zuckerberg followup questions in a Tuesday letter, including asking for a full list of device manufacturers Facebook shared data with and details of how Facebook disclosed those sharing arrangements to consumers.
• "We look forward to addressing any questions the Commerce Committee has," a Facebook spokesperson said.
• Senate Judiciary Committee Chairman Chuck Grassley and top House Energy and Commerce Committee Democrat Frank Pallone want the Federal Trade Commission to look at the issue. Facebook critics say that the data sharing violated a previous settlement with the agency, which is already digging into the company's practices in light of the Cambridge Analytica scandal.
• At an Axios event Tuesday morning, Senate Intelligence Committee Vice Chair Mark Warner asked whether Facebook had shared user data with Chinese telecom providers like ZTE and Huawei — which lawmakers worry are are too close to China's government.