Based on the overhead-view sketch, the English carmaker believes that The Force 1 is "strikingly similar to several of Aston Martin's cars, including the DB10" from the movie Spectre. At the same time the carmaker's letter to Fisker admitted that it doesn't know what the final design will look like, but it appears that the carmaker's intent to "protect its valuable rights if necessary" could not make way for patience. Or perhaps Aston Martin is trying to prevent another Thunderbolt episode before it starts. That incident last year involved the carmaker suing Fisker over his reimagined Vanquish, with the two settling the matter out of court.
Fisker says The Force 1 has isn't based on an Aston Martin, and as part of the lawsuit submitted a design breakdown of both the DB10 and The Force 1. Fisker's latest is apparently in partnership with VL Automotive, the company that's been threatening to release a V8-powered Karma sedan for years now, and the Detroit show organizers say they've been working with VL, not Fisker.
The lawsuit seeks the $100 million for punitive and compensatory damages and court costs, alleging that Aston Martin's actions "would subject [Fisker] to public humiliation, embarrassment in the industry, and significant financial losses." The public allegations go even further, Fisker's lawyer Jonathan Michaels saying that the English brand, "In an effort to protect itself from further market erosion... conspired and devised a scheme to stomp out Henrik Fisker's competitive presence in the luxury sports car industry."