Doofenshmirtz Evil Amalgamated is the main antagonistic faction in the Phineas and Ferb episode "Steampunx". It is the 1903 equivalent (and possible ancestor) of Doofenshmirtz Evil Incorporated led by Professor Von Doofenshmirtz.
Doofenshmirtz Evil Amalgamated was founded by Von Doofenshmirtz as his own hideout, but it was not until he came up with his next plot to destroy the Danville World Fair by creating and utilizing a giant robotic swan. When Von Doofenshmirtz's nemesis Swerry the Swan arrives to the building, Von Doofenshmirtz compensates this by having his right-hand Pneumatic Pnorman to trap him before explaining his scheme to him.
Von Doofenshmirtz then Swerry to be tied into a railroad track before initiating his scheme to wreak havoc on the World Fair. However, Swerry escapes and saves the day by plugging the giant robotic swan with corn, causing it to explode and sending Von Doofenshmirtz up into the air.
It is implied that Doofenshmirtz Evil Amalgamated was closed down afterwards, even when an extremely old but alive Von Doofenshmirtz crashed down to the present, wondering how long was he up in the sky.