Poland has been defined a key growth area for Raisio, which has been active in the Polish margarine market for 10 years.
The deal gives Raisio rights to sell Obory's products, as well as its range of Benecol brand cholesterol-lowering foods.
While Poland's population of 38.6 million may have lower purchasing power than west European nations, the country has heart disease mortality rates on a par with many north European nations.
Raisio's stake in the Polish firm could also help future business in neighbouring east European markets.
Obory is the market leader in drinkable, JOVI-branded yoghurts in Poland with turnover of around €12 million.