Rivian Automotive Inc. sank 17 per cent in U.S. premarket trading after a media report that Ford Motor Co. is selling 8 million of its shares in the electric-pickup maker at a discount.

Ford’s sale is being handled by Goldman Sachs Group Inc., CNBC’s David Faber said in a tweet.  

The U.S. manufacturer owns about 12 per cent of the electric-vehicle hopeful, or just under 102 million shares after taking a stake prior to Rivian going public last year. An insider lockup period expired Sunday after the November share sale that saw the company’s market value briefly top US$100 billion making the developer more valuable at the time than Ford and General Motors Co. 

Rivian shares have since plunged after its pickup launch was slower than investors expected.

JPMorgan Chase & Co. is also selling a block of 13 million to 15 million shares in the manufacturer for an unknown seller, Faber reported, citing unidentified people. Both blocks are priced at US$26.90 -- a discount of 6.7 per cent to Friday’s close.

Irvine, California-based Rivian is a high-profile, well-funded newcomer to the growing pack of EV manufacturers. The IPO was the sixth biggest in U.S. history, generating more than US$13 billion to fund growth. However, Rivian has struggled to ramp production of its products at an existing plant in Normal, Illinois, due to supply-chain pressures.