Usually when a large company owns a one word .com they tend to hold onto it even after a merger. Continental.com was once owned by Continental Airlines who merged with United back in 2012.
The company has always looked out for domain names infringing their ip. They filed UDRP’s at the beginning of the 2000’s for names like continentalairlines.biz and the typo wwwcontinentalairlines.com.
Continental.com looks to have moved to Continental AG in August of 2017, Continental AG is the German company that owns the popular Continental tire brand.
Interestingly the airline allowed Continental.org to just expire and it was auctioned at NameJet, it sold for $1,009. Interestingly the winner listed it at Sedo for just $2,888 and who came along 6 months later and purchased it? That’s right Continental AG.
Continental.net was also allowed to drop, it sold on NameJet for $810. It is parked at Sedo.
In my opinion United screwed up by allowing ContinentalAirlines.com to expire. It was auctioned at NameJet and went for $787 in 2015.