See Brad & Angelina's Divorce Docs

TMZ obtained a copy of Angelina Jolie's divorce petition ... filed Monday in Los Angeles.

We broke the story ... she cited irreconcilable differences in the split from Brad Pitt, and requested sole physical custody of their 6 children.

For his part ... Brad says, "I am very saddened by this, but what matters most now is the well being of our kids."

As we've reported ... the breakup is 100% over her concerns about Brad's parenting.