Filbert, Inc. was a company based in Baltimore, Maryland, United States that produced margarine and butter substitute products, including Mrs. Filbert's Margarine and I Can't Believe It's Not Butter!.
The company was founded by John H. Filbert, who died in 1917.
[2][3] In 1972, Central Soya acquired the privately owned company, which at that time had reached annual sales of $63 million and was the largest privately owned manufacturer in Baltimore.
[4][5] In 1979, Filbert invented I Can't Believe It's Not Butter!
[6] Unilever acquired Filbert in 1986 for $23 million in order to add East Coast U.S. manufacturing capacity.