It is possible to have more than one trademark for a given word, and Apple has (at least) two for "retina": http://tess2.uspto.gov/bin/showfield?f=doc&state=40

It is possible to have more than one trademark for a given word, and Apple has (at least) two for "retina": http://tess2.uspto.gov/bin/showfield?f=doc&state=4003:o8la6.2.7 http://tess2.uspto.gov/bin/showfield?f=doc&state=4003:o8... http://tess2.uspto.gov/bin/showfield?f=doc&state=4003:o8la6.2.5 http://tess2.uspto.gov/bin/showfield?f=doc&state=4003:o8... The one not mentioned in the article is for "Computers; computer hardware; computer displays; computer software; handheld mobile digital electronic devices used as a telephone, handheld computer, personal digital assistant, electronic organizer, and electronic notepad, and used to access the Internet, electronic mail, and other digital data".