The San Francisco Chronicle joined with nine other news organizations and a First Amendment group Monday to urge that most of the upcoming trial between Waymo and Uber over self-driving car technology remain open to the public and press.

Waymo, the Alphabet unit which originated in Google’s self-driving car project, last week asked Judge William Alsup to close portions of the trial, scheduled to begin on Oct. 10. Waymo has accused rival Uber of using Waymo’s proprietary technology for a key, laser-based sensor called lidar, which helps autonomous vehicles sense their surroundings.

Waymo argued that the courtroom be closed for any in-depth discussion of the company’s trade secrets and Uber’s alleged use of them. Waymo also wants to close the courtroom and seal the record on any discussion involving Waymo’s internal financial details, business plans, partnerships with other companies and employee salaries and bonuses.

In a motion to intervene filed Monday, an attorney representing the coalition of media organizations, which includes The Chronicle’s parent company, Hearst, argued that Waymo’s request is far too broad.

“Because the heart of Waymo’s case is that defendants misappropriated trade secrets, accepting such a broad and undefined claim could result in the closure of a large portion of the trial,” wrote attorney Steven Zansberg of Ballard Spahr LLP, representing the news organizations.

The Chronicle and Hearst were joined in the motion by the Associated Press, Bloomberg, Buzzfeed, MediaNews Group, Dow Jones, The First Amendment Coalition, Gizmodo Media Group, The New York Times Co., Reuters and Vox Media.

The news organizations stopped short of insisting that the entire trial remain open, saying that sealing “some limited portion” could be justified.

But any such closure should be very narrowly focused, they argued. And they said that Waymo had not demonstrated the substantial probability of harm that would justify closing part of the testimony. Nor, they said, has the company explored whether any “less restrictive” steps, short of closing the courtroom, could address its concerns.

Alsup, with the U.S. District Court for the Northern District of California, is scheduled to consider the news organizations’ motion on Tuesday. He will also discuss with opposing lawyers a separate request from Waymo to delay the trial until December.

The lawsuit, filed in February, pits two of the most prominent Bay Area companies racing to build self-driving cars against each other. And it could have implications for how that race develops.

“Given the nature of the claims at issue, affecting the future of an industry and technology capable of revolutionizing how humans travel by car, the trial will undoubtedly address issues of significant and legitimate public concern,” Zansberg wrote.

A Waymo spokeswoman said Monday that the company only wanted the courtroom closed in a limited number of circumstances.

“Waymo welcomes a public trial and we will work with all parties to minimize closed courtroom time,” the company said.

David R. Baker is a San Francisco Chronicle staff writer. Email: dbaker@sfchronicle.com Twitter: @DavidBakerSF