Sunday, March 6, 2011

Are system claims better than method claims for computer-implemented inventions?

If you have a computer-implemented invention, are method claims more valuable than system claims, or vice versa? I submit that system claims are the clear winner, at least since January 2011.

Method claims are clearly subject to scrutiny under Bilski. (Bilski v. Kappos, 30 S. Ct. 3218,  (2010).) But it's possible that courts won't apply Bilski to other types of claims – the question is still open. Score: System 1; Method 0.

Direct infringement of a method claim requires that a single party performs all steps. Joint liability for multiple parties is possible, but the standard is high. The Federal Circuit recently clarified this high standard for joint liability in Akamai Techs., Inc. v. Limelight Networks, Inc. (December 20, 2010): "there can only be joint infringement when there is an agency relationship between the parties who perform the method steps or when one party is contractually obligated to the other to perform the steps." Score: System 2; Method 0.

In contrast, the Federal Circuit recently held that system claims which include elements in the possession of more than one actor are analyzed differently. In Centillion Data Sys., L.L.C. v. Qwest Commc'ns Intl, Inc. (January 20, 2011), the court held that "to 'use' a system for purposes of infringement, a party must put the invention into service, i.e., control the system as a whole and obtain benefit from it." The system claim in Centillion involved components operated by a telephone billing provider (the back end) as well as components operated by a customer of the provider (the front end). The court found that customer actions controlled the system as a whole, so that the customer was a direct infringer. Score: System 3; Method 0.

The only reason I can think of for including a method claim in a computer-implemented application today is the uncertainty of case law. It's always possible that when a patent issuing today is litigated many years in the future, new case law will make method claims the more valuable ones.


  1. My personal prejudice is that systems claims are always better than "methods" claims, except where the invention is truely a process. Systems claims (should) point to tangible (therefore identifiable for infringement purposes) elements. Methods claims, particularly business methods, tend to point to human actions.

    Of course, I'm generally prejudiced against "methods" claims in general. I sort of reject the now-accepted equivalence of a method (a way of doing something) and a process (the actual doing). Again, "methods" are what humans do (perhaps assisted by a machine) while machines often are the actors in a process. That's why factories have process control systems, not method control systems.

    But that's a discussion for another time.

  2. This is like asking is an apple better than an orange. It all depends on what you're looking for that day. Did you invent a system? Then claim a system. Did you invent a method? Then claim a method.

  3. >Did you invent a system? Then claim a system.
    >Did you invent a method? Then claim a method.

    I submit that the inventions I was referring to -- computer-implemented inventions -- can almost always be properly characterized as *either* a system or a method.

    The kinds of inventions I'm referring to are basically directed to new *functionality*. These functions can easily, and quite naturally, be described as methods.

    But the functionality is implemented by some sort of system or device. In either software (processor executing instructions), specialized hardware (ASIC, SoC, etc.), or some combination of the two.

    The choice of implementation is dictated by market forces. Stuff that was once done in software (TCP stack) can be done in hardware (e.g., TCP offload engine). And as processors become faster and have more specialized instruction sets, the converse is also true.

    If I invent new functionality that could be realized in either software or silicon, is it a system or a method? I submit that it's both.


  4. Bruce Horwitz said:
    >I'm generally prejudiced against "methods"
    >claims in general.

    Bruce, good to have you back.

    Yes, I recall reading a good post on your blog explaining your position:

  5. What about all that case law that system claims are to be interpreted as means plus function? Method claims are not usually interpreted as step plus function without the invoking language, but system claims are much more vulnerable to it, leading to narrower scope, and vulnerability to 112 invalidity. I'd say that's 2 BIG points in favor of method claims, and I like to have both system and method claims.

  6. "That's why factories have process control systems, not method control systems."

    I don't see the relevance of this clever phrase. Why don't we just write process claims if factories have process control systems.

    Method claims have their uses. For example method claims can reach off shore usages via 271(g) while device/systems claims cannot.

  7. Don't forget about Beauregard (computer-readable medium (CRM)) claims. CRM claims can often be written to have similar scope (if not essentially identical scope) to a method claim, but do not require that one person perform all the operations. In fact, a recent Fed. Cir case confirms that a device (CRM) only need be shipped with software capable of performing the steps in order to infringe. (See Finjan v. Secure Computing)

    Personally I want a patent to have method, system and CRM claims when protecting a computer-implemented invention. The main potential issue with the system claims isthe potentially limiting structure that is either recited or with be read into the claim on construction.