The acquisition comes two years after Henkell launched its own distribution company in the UK.
It said the main focus of its investment in Copestick Murray would be to develop its Mionetto prosecco brand in the UK market.
Chief executive Andreas Brokemper said: “In the US, we have played an important role in shaping and creating the prosecco trend and we are now the market leader.
“We are fuly confident that the Copestick Murray team, together with our own sales organisation, will establish the Mionetto brand in the UK as well.”
Copestick Murray co-founder Robin Copestick added: “The financial backing from Henkell will allow us to continue our remarkable growth.
“The partnership is a perfect fit for our company. Its speciality in making sparkling wines all over Europe is very exciting for us.
“Sparkling wine is a growth category in the UK and, up until now, we were under-represented in this arena.”