Source code ch.04: Answering questions

Source Code & Software Patents: A Guide to Software & Internet Patent Litigation for Attorneys & Experts
by Andrew Schulman (
Detailed outline for forthcoming book


Chapter 4: Using source code to answer patent litigation questions

4.1 Goals of the source code examination: Extraction or translation?

  • Extraction: see chapter 13 on source-code examination purposes & approaches
  • Translation: see also chapter 8 on expert’s role as “translator”

4.2 Answering who/what/when questions

  • 4.2.1 Who? (Who wrote this code?; Who performs this step?: determining all steps carried out by single entity)
  • 4.2.2 What?
  • 4.2.3 When? (When was this code written, when does this operation occur, etc.)
  • 4.2.4 Where? (Where is this step performed, etc.: relevant e.g. to importation ITC action)
  • 4.2.5 Why? (Why was this feature implemented in this particular way?: advantages of patented techniques are relevant to damages)
  • 4.2.6 How?
  • 4.2.7 How much/often? (How often is this code executed?: may be relevant to damages; How many are there?: relevant to e.g. “plurality” claim limitations or “without” absence claim limitations)

4.3 Source code as evidence for contentions & defenses

  • Offensive and defensive use of source code
  • 4.3.0 Interaction of claim type (apparatus/method/system/medium) with infringement type (make/use/sell/offer/import)
  • 4.3.0B Relation of source code to business methods, signal claims (Nuijten), and data-structure claims (Lowry)
  • 4.3.1 Direct literal infringement
  • Means plus function (“means for”) claim elements under 112(6), and other functional claiming
  • 4.3.2 Doctrine of equivalents: separate showing of function, of way, and of result; insubstantial differences
  • 4.3.3 Indirect (contributory and inducement) infringement
  • 4.3.4 Willful infringement
  • 4.3.5 Non-infringement [note difference between rebutting asserted infringement on the one hand, and affirmatively declaring (e.g. declaratory judgment action) non-infringement, i.e. absence of infringement, on the other hand?]
  • BOX: Making molehills out of seeming mountains
  • 4.3.6 Prior user & intervening rights
  • 4.3.7 Damages (see chapter 30)
  • 4.3.8 Non-infringing alternatives & design-around (see chapter 30)
  • 4.3.9 Injunction (see chapter 30)
  • 4.3.10 Practicing/working (for ITC domestic industry technical prong; eligibility for injunctive relief under eBay v. MercExchange; etc.; see chapter 30)
  • 4.3.11 Claim construction (Markman): source code is NOT coming into the Markman hearing (claim construction is not supposed to be based on consideration of the accused instrumentality), but may drive the parties’ positions in claim construction
  • 4.3.12 Invalidity [while not entirely relevant to source code, this is an appropriate place to discuss subject-matter requirements for software patents, under Alice v. CLS Bank and USPTO post-Alice guidelines, and post-Alice case law e.g. DDR Holdings v.; Loyalty v. American Airlines; Helios v. Spectorsoft; Cal. Inst. Tech. v. Hughes; Amdocs v. Opennet; Enfish v. Microsoft; etc.]
  • Anticipatory prior art [see also invalidity charts in chapter 26]
  • Obviousness
  • Priority (pre-AIA)
  • On-sale & public-use bars
  • Inadequate disclosure: enablement, undue experimentation, written description, indefiniteness [discuss source code particularly as it relates to 112(6) means-plus-function claiming; also note dangers of functional claiming (even when it does not explicitly employ “means for…” language)]
  • 4.3.13 Post-grant review
  • 4.3.14 Equitable considerations
  • 4.3.15 Expert’s source code (including assessing models of economics experts)

4.4. Likely contents of source code production — see chapter 15

Print Friendly, PDF & Email