Legal Question in Business Law in California

First off, YOU can't serve anyone if you are suing them. Process must be served by someone over 18 and not a party or real party in interest to the case. Second, technically each copy of the summons must be filled out as to ONE party. However, even if they technically might be able to quash service on that basis, you could just serve them again with two copies of the summons. If you are really concerned about this, you should use a professional process serving company, such as OneLegal if you are comfortable working online, or a local service if you prefer the personal touch. If you can't afford a process server fee, quite frankly, you are going to be blown out of the water with the other costs of proceeding with your case, which will run several thousand to tens of thousands even for a fairly simple case.

Without detracting from Mr. McCormick's answer, let me point out that "as a business" is way too vague a term upon which to provide you with any assistance. A "business" can mean a sole proprietorship, a corporation, a partnership, an LLC, and possibly other kinds of organization.

If the business is a sole proprietorship run by the person being sued as an individual. ordinarily one summonts should be enough, and with only one box checked. A business conducted as a proprietorship is not distinct, legally, from the person running it.

If the business is not a proprietorship, you'd need to sue it as an additional party named in the suit, and serve it with a separate and distinct summons addressed to it and it alone. Sure, it's the same lawsuit, but each defendant (e.g., the "person" and the non-person "business") must receive a summons addressed to him/her/it and no others.

In other words, a proprietorship business is legally indistinguishable from its proprietor, but any business that's an entity must be named as a defendant and served separately.