When suing in a claim, how do I write it?

You don't sue insurance companies in auto cases. you sue the owner and the driver of the car. the insurance cos come in to defend. you can go to the courthouse and look at some other cases for form and style but if you have a serious case you should have a lawyer. you wont do well by yourself. If you have a nuisance case or just want to play it that is OK I guess, but is a waste OF TIME

If you are actually filing a law suit, it is against the defendants and not their insurance companies, so you do not mention the names of the insurance companies. If you mean you are filing a claim with the insurance company and not yet a lawsuit, then you send the letter to the insurance company "re: Jane Doe, date of accident xx/xx/xxxx1st? Street and 4th avenue, Oakland, California.

If you are filing in Georgia, except in a few rare circumstances, you are not permitted to name an insurance company in the style (heading) of the lawsuit. For example, if Bob Jones is suing John Smith for causing an automobile wreck and Mr. Jones is insured by ABC Ins. Co. and Mr. Smith is insured by XYZ Ins. Co., the style of the case will read: Bob Jones. Plaintiff, v. John Smith. Defendant. ABC Ins. Co and XYZ Ins. Co. will not be mentioned in the style of the case. Despite this, to the extent of available insurance coverage, XYZ Ins. Co. will cover Mr. Smith.