It's official now! Government tax credit is not considered a state subsidy under WTO.

http://www.channelnewsasia.com/news/business/wto-reverses-ruling-against-boeing-777x-tax-credits-9184910

Many countries will use the tax credit to boost its competitiveness now as WTO doesn't consider tax credit as a state subsidy.

WTO has set the precedent for all to follow.  Good job!