Redstone, however, will not be required to give testimony, the judge decided.
National Amusements Inc, the Redstone family's holding company, and CBS are in the midst of a high-stakes legal dispute over control of the company and its potential merger with Viacom Inc, also majority-owned by NAI. Shari Redstone, the daughter of Sumner, has pushed to combine Viacom with CBS.
The health and mental faculties of Sumner Redstone, the founder and chairman emeritus of Viacom, and the majority owner of NAI, are a flashpoint for dispute in the battle for control.
"We are very pleased with the court's ruling today, which will now allow us to conduct appropriate discovery from National Amusements on the issue of who controls NAI," CBS said in a statement, adding that the video of Redstone would be kept confidential.
National Amusements declined to comment.
CBS had pushed to have the tape, which could end up as evidence in the trial, included for review, while NAI has previously said that the recording broke California law because Redstone did not know he was being filmed.
The contents of the video have not been made public. A source with knowledge of the situation said the video was taken by a CBS board member, is several minutes long and shows Sumner Redstone's physical and mental state.
National Amusements must produce certain documents requested by CBS, according to court filings.
CBS said it will also be able to secure National Amusements' documents relating to the 2016 ousting of five Viacom directors, including then-CEO Philippe Dauman.
The CBS board had approved a dividend earlier this year that would dilute the Redstone family's majority voting rights in the company, in an attempt to prevent the merger with Viacom.
(Reporting by Jessica DiNapoli; additional reporting by Liana B. Baker, Editing by Rosalba O'Brien)
By Jessica DiNapoli