Danity Kane Reunion -- Screw Diddy, We're Reuniting Without Him

Diddy's gonna be pissed -- TMZ has learned, Danity Kane (the band he created and later destroyed) is reuniting ... without his blessing.

Four original members of the group -- Aubrey O'Day, Shannon Bex, Dawn Richard, and Aundrea Fimbres -- grabbed lunch today in L.A. with a new manager to discuss the reunion ... and sources tell TMZ, it's definitely happening. We're told they plan to record and tour.

We asked the girls if Diddy was involved this time around ... their response -- "Who's that?"

You'll recall, Diddy created the group back in 2005 during "Making the Band 3" and later signed them to Bad Boy Records. In 2009, Diddy fired the entire group (with the exception of Dawn Richard).

It's unclear who really owns the name "Danity Kane" -- but we're told the girls are going to use it regardless. Translation: you can expect a nasty legal battle.

As for why Diddy eventually gave the group the chop -- there have been all kinds of rumors ... but we're told the girls felt Diddy was screwing them big-time in the money department.

We called Diddy's people -- so far ... no response.