Legal Definitions - all-steps rule

The all-steps rule is a principle in patent law that helps determine if a patented method or process has been directly copied, or "literally infringed." For a company or individual to be found literally infringing a patented process, their own process must include every single step, or an equivalent of each step, as described in the original patent claim. If even one step is missing or performed in a non-equivalent way, there is no literal infringement under this rule.

Here are some examples to illustrate the all-steps rule:

• Example 1: Pharmaceutical Manufacturing Process

  Imagine a pharmaceutical company holds a patent for a specific method of synthesizing a new drug. This patented method involves five distinct steps: (1) mixing compound A with solvent B at a specific temperature, (2) adding catalyst C, (3) heating the mixture to 150°C for 3 hours, (4) cooling rapidly to 0°C, and (5) filtering the resulting solution through a specialized membrane. A competitor develops a similar drug using a process that includes steps (1), (2), (3), and (5), but instead of rapid cooling to 0°C, they allow the mixture to cool slowly to room temperature (a non-equivalent step). Under the all-steps rule, the competitor's process would likely not be considered a literal infringement because it omits step (4) or an equivalent of it, even if the final product is similar.

• Example 2: Data Processing Algorithm

  Consider a patent for a unique algorithm designed to optimize data transfer over a network. The patented method specifies three critical steps: (a) compressing data using a proprietary algorithm, (b) segmenting the compressed data into fixed-size packets, and (c) encrypting each packet with a dynamic key before transmission. A rival software company develops a network optimization tool that performs steps (a) and (b), but for encryption, it uses a standard, publicly available encryption protocol rather than the dynamic key encryption (step c) or an equivalent. Because the rival's method does not include the unique encryption step (c) or an equivalent, it would not literally infringe the patented algorithm under the all-steps rule.

• Example 3: Food Preservation Technique

  A food science company patents a novel method for preserving fresh berries, involving four steps: (i) washing berries in a specific antimicrobial solution, (ii) drying them using a pulsed air system, (iii) coating them with an edible, oxygen-impermeable film, and (iv) storing them in a vacuum-sealed container. A local farm adopts a preservation technique that includes steps (i), (ii), and (iv), but instead of coating the berries with the patented film, they simply spray them with a common antioxidant solution (a non-equivalent step). According to the all-steps rule, the farm's process would not literally infringe the patented method because it omits step (iii) or an equivalent, even if the berries are preserved for a longer time.