Boeing Co. BA, -3.39% and Brazil-based Embraer S.A. ERJ, +2.80% EMBR3, +2.31% announced Thursday a partnership to help both companies accelerate growth in the aerospace market. Boeing's stock rose 0.4% in light premarket trade, while Embraer's U.S.-listed shares were indicated up over 4%. The companies are planning to form a joint venture, of which Boeing will have an 80% stake. The deal would value Boeing's ownership in the JV at $3.8 billion, and value 100% of Embraer's commercial aircraft operations at $4.75 billion. Boeing expects the partnership to add to earnings beginning in 2020, and create annual cost synergies of about $150 million by the third year. Boeing's stock has rallied 13% year to date through Tuesday, while Embraer shares have climbed 9.5% and the Dow Jones Industrial Average DJIA, +0.19% has slipped 2.2%.