The 10% figure, first reported by Bloomberg, is lower than the 20% or so mentioned by sources at the very start of the discussions.
The sources insisted on anonymity, as the discussions, which were still ongoing on Thursday, are confidential.
A Horse spokeswoman declined to comment, while no immediate comment could be obtained from Geely or Aramco.
The Saudi oil group had signed a letter of intent in March 2023 with a view to eventually becoming a minority shareholder in the JV, which was founded on May 31 last year. (Gilles Guillaume reports, with Norihiko Shirouzu in Austin, Zoey Zhang in Shanghai and Maha el Dahan in Dubai, edited by Jean Terzian)