Utilize the input text as a context reference, choose the right relationship between Durex 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.

This week's bubbly trading update reinforced this view, and allowed it to continue the 12% share price gain enjoyed during the past four weeks -- the London firm saw like-for-like sales advance 5% during January-June, with product rollouts like its Scholl Express Pedi and Durex Real Feel helping to drive shopper interest.

Answer: headquarters_location