The data is listed on a U.S. Senate website containing financial disclosures from Senate members.

Feinstein, who serves as ranking member of the Senate Judiciary Committee, and her husband sold between $1.5 million and $6 million in stock in California biotech company Allogene Therapeutics, between Jan. 31 and Feb. 18, The New York Times reported.

Feinstein defended herself in a series of tweets on Friday, saying she has "no control" over her assets and the stocks in question were her husband's transactions.

"During my Senate career I've held all assets in a blind trust of which I have no control. Reports that I sold any assets are incorrect, as are reports that I was at a January 24 briefing on coronavirus, which I was unable to attend," she tweeted.

"Under Senate rules I report my husband's financial transactions. I have no input into his decisions. My husband in January and February sold shares of a cancer therapy company. This company is unrelated to any work on the coronavirus and the sale was unrelated to the situation."