As of March 27, the patents are no longer an issue: https://github.com/NTRUOpenSourceProject/NTRUEncrypt/issues/11 > The patents are intended to also be public domain. To be specific, we will > not take any enforcement action against anyone for any > use of the indicated > patents on or after March 27th, 2017. (And "March 27th, 2017" means "March > 27th, 2017 anywhere in the > world").
