Gap stock is up by 39 percent as of this morning after Kanye West announced a multiyear partnership with his brand, YEEZY. According to CNBC, news of the collaboration has brought more than $1.4 billion to Gap’s market cap of $3.8 billion.

The YEEZY Gap deal is reportedly for 10 years, and it will include modern elevated basics for men, women, and children at accessible price points. The clothing line, which is set to debut in 2021, will be sold in stores and online.

Kanye revealed the collaborative partnership in a tweet earlier today. The rapper/designer previously worked for Gap as a teenager in Chicago, after which he shadowed the brand’s then-creative director Patrick Robinson in 2009.

“We are excited to welcome Kanye back to the Gap family as a creative visionary, building on the aesthetic and success of his YEEZY brand and together defining a next-level retail partnership,” said Mark Breitbard, Global Head of Gap Brand.

Gap has disclosed that YEEZY will receive royalties and potential equity related to sales.