StarfieldWiki:News/Starfield Trademarked
Starfield Trademarked — March 22, 2013
ZeniMax filed for a trademark for Starfield on March 22nd, 2013. The trademark covered "Computer game software for use with computers and video game consoles; downloadable computer game software offered via the Internet and wireless devices; computer game software for use with on-line interactive games, clothing, namely, T-shirts, shirts, sweatshirts, pants, jackets, fleece pullovers; headwear, namely, hats; footwear, namely shoes and sneakers, and computer and video game user instruction manuals; magazines, books, and pamphlets concerning video games; computer and video game strategy guide books and magazines; trading cards, maps, posters, advertisement boards of paper or cardboard, art prints". This suggested that they were going to work on creating a game or franchise called Starfield in the near future.
The official announcement would come more than five years later on June 10th, 2018. You can see these initial trademarks here, here, and here.