A recent ruling in a closely watched patent infringement case involving several patents relating to methods for processing ethanol byproducts — and specifically recovering oil from thin stillage — could significantly impact the ethanol production industry.

Case Background and Ruling

The case involved several patents owned by the plaintiff, GS CleanTech Corporation, including: U.S. Patent No. 7,601,858 ('858 Patent); U.S. Patent No. 8,008,516 ('516 Patent); U.S. Patent No. 8,008,517 ('517 Patent); and U.S. Patent No. 8,283,484 ('484 Patent) (collectively, the '858 Patent Family). GS CleanTech also asserted U.S. Patent No. 8,168,037 (the '037 Patent) against a handful of defendants. 

The defendants, collectively and individually, moved for summary judgment on numerous grounds, including non-infringement and invalidity. The district court concluded that numerous defendants did not infringe several of the asserted claims.

However, the court's more significant rulings were those regarding invalidity, in particular:

1. Three of the patents in the '858 Patent Family — the '858 Patent, the '516 Patent and the '517 Patent — are invalid under 35 U.S.C. § 102(b) because the patented technology was offered for sale more than one year before the invention date.
2. All four patents in the '858 Patent Family and the '037 Patent are invalid as obvious under 35 U.S.C. § 103 in view of a combination of known prior art references.
3. Several other claims in the '858 Patent Family and the '037 Patent are invalid on numerous additional grounds, including as indefinite and for lack of enablement under 35 U.S.C. § 112 and for failure to name the correct inventors pursuant to 35 U.S.C. § 102(f).

Significance for Ethanol Producers

The significance of the court's invalidity rulings is that the asserted claims of all five of these patents — the '037 Patent and the four patents in the '858 Patent Family — are now unenforceable against anyone (unless GS CleanTech is successful on appeal). Accordingly, those in the industry that have been watching this case or tailoring their processes in a way to avoid GS CleanTech's patents can consider whether to re-evaluate their strategy going forward. However, as noted above, any company tracking this lawsuit and the status of GS CleanTech's patents should still pay close attention to whether GS CleanTech appeals these rulings and, if so, the results of that appeal. 

Summary of Claims Asserted

The following chart summarizes the various claims that GS CleanTech was asserting against numerous defendants for each of foregoing patents.