## Facts

- Grain Processing Corp. owned U.S. Patent No. 3,849,194 covering certain maltodextrins and related production processes, and sold maltodextrins under the brand “Maltrin.”
- American Maize-Products Co. competed in the maltodextrin market and sold a product known as “Lo-Dex 10.”
- The district court found American Maize infringed and entered injunctive relief; the remaining dispute concerned damages.
- Grain sought lost-profit damages, arguing it would have made the sales American Maize made but for the infringement.
- American Maize argued it could and would have produced a noninfringing substitute using a glucoamylase-based process; glucoamylase was commercially available during the infringement period, though American Maize did not switch until 1991, largely due to higher cost.
- The district court found the glucoamylase-based process was technically feasible and obtainable during the infringement period and would have produced a product acceptable to purchasers of the infringing Lo-Dex 10.
- Based on the availability and acceptability of this noninfringing alternative, the district court denied lost profits and awarded a 3% reasonable royalty on infringing sales.
- Grain appealed solely the damages ruling denying lost profits.

## Issues

1. Whether the district court clearly erred in finding that American Maize proved an available and acceptable noninfringing substitute during the infringement period, thereby rebutting “but-for” causation required for lost profits.

## Decision

- The Federal Circuit affirmed the judgment denying lost profits and awarding a 3% reasonable royalty.
- The court held that a noninfringing alternative may be “available” even if it was not then sold or practiced commercially, so long as it was feasible and obtainable and the infringer showed it would have used it in the but-for world.
- The court upheld the district court’s finding that the glucoamylase-based alternative was acceptable to customers of the infringing product.
- Applying clear-error review to these factual findings, the court found sufficient support in the record and declined to disturb the district court’s causation determination.

## Legal Principles

- Lost-profit patent damages require proof of “but-for” causation: the patentee must show it would have made the infringer’s sales absent infringement.
- Proof that acceptable noninfringing alternatives were available can rebut the inference that the patentee would have captured the infringer’s sales.
- “Availability” of a noninfringing alternative does not require contemporaneous commercial sales or actual use; technical feasibility and the ability to implement the alternative during the infringement period may suffice.
- “Acceptability” turns on whether purchasers would have viewed the noninfringing alternative as an adequate substitute for the infringing product.
- Appellate review of district-court findings on availability, acceptability, and causation in damages is for clear error.

## Conclusion

Because American Maize proved it could and would have switched to an acceptable, feasible noninfringing production method during the infringement period, Grain failed to establish the necessary but-for causation for lost profits, and its recovery was properly limited to a reasonable royalty.


Grain Processing Corp. v. American Maize-Prods. Co., 185 F.3d 1341 (Fed. Cir. 1999)