Utilize the input text as a context reference, choose the right relationship between Inmarsat and London from the options. Options: product/material produced, manufacturer, distributed by, industry, position held, original broadcaster, owned by, founded by, distribution format, headquarters location, stock exchange, currency, parent organization, chief executive officer, director/manager, owner of, operator, member of, employer, chairperson, platform, subsidiary, legal form, publisher, developer, brand, business division, location of formation, creator.

Inmarsat (LSE: ISAT.L - news ) ’s shares were rocketing in London alongside the launch of its third Global Xpress satellite, which went into orbit yesterday to help complete the firm’s next-generation broadband internet network.

Answer: headquarters_location