Salesforce is taking over 6 more floors in one of London's tallest skyscrapers

US cloud giant Salesforce is expanding its UK headquarters in one of London's tallest skyscrapers.

The San Francisco enterprise software company, which has a market cap of $77 billion (£52.7 billion), announced the office expansion on Thursday at its largest customer event outside the US, alongside several other investments into the UK.

The expansion will see Salesforce go from occupying four floors at 110 Bishopsgate to 10 floors, a Salesforce spokeswoman told Business Insider, adding that some floors are still under construction. Salesforce has not disclosed which floors it is taking or when they will be fully occupied.

Salesforce tried and failed to officially rename the building- widely known to Londoners as Heron Tower - after itself in 2014. The company signed a 15-year naming rights deal with Heron International in May 2014 but City of London council members voted in September 2014 in favour of naming the skyscraper "110 Bishopsgate," after the building's street address.

Several of the building's existing tenants, including failed startup Powa Technologies, were unhappy over the proposed Salesforce rebranding. At the time of the name change, Ant Sharp, Powa Technologies' deputy chair, reportedly said it was "at best rude and at worse is contrary to the law and leases we signed."

Despite not gaining official naming rights, Salesforce and Heron International still refer to the building as Salesforce Tower. The company's branding can be found in the lobby of the skyscraper and a website with the domain name www.salesforce-tower.com has also been created.

Salesforce also announced that it has invested in three UK cloud startups since last October, when it pledged to spend $100 million (£65 million) on European enterprise startups over the next five years. The three UK startups include NewVoiceMedia, Qubit, and Digital Genius.

Andrew Lawson, managing director of Salesforce's UK & Ireland business, said in a statement: "Salesforce is seeing phenomenal momentum in the UK and we are excited to increase our investment in this region to support our growing customer base."