The brief, which the Chime agency began work on in April, includes an EMEA hub role, UK PR, customer advocacy and social media.
For the previous three years, Veeam had worked with Octopus on a narrower remit, which did not include customer advocacy or digital, but the agency declined to repitch.
James Warnette, head of EMEA corporate comms at Veeam, said: "Hiring Harvard was a unanimous decision amongst our internal panel. It was an audacious pitch response, one that demonstrated a good understanding of our brand, our business challenge, strong sector insights, as well as capturing our imagination with their creative thinking."
Harvard CEO Louie St Claire said Veeam was "on course to be a billion-dollar business this year and is loved by its users, but relatively unknown amongst a mainstream media audience". It also plans to become a $2.2bn business by 2022.
Octopus CEO Jon Lonsdale said of the decision not to repitch: "We had a great few years with Veeam and it’s a really strong case study for us - but we decided that the account team would appreciate a fresh challenge so decided not to repitch. We wish them all the best for their future programmes."
Veeam works with a variety of different agencies globally, including Lewis in the US, Porter Novelli in Mexico, H+K in Germany, OneChocolate in France and recently appointed Prima Pagina in Italy.
The firm recently lost CMO Kate Hutchison after nine months in the role. Hutchison, who is said to have left to pursue "external opportunities", was not involved in the hiring of Harvard.
PRWeek readers may recall that one of Veeam's US-based office pets was voted the industry's second cutest in a 2016 poll.