Reggie Jackson steal no-call/out-of-bounds
Contact like this is very hard to adjudicate. The difference between incidental and illegal contact (and hence what constitutes a foul) is often up the the judgement of the referee. However the rule says that, "Contact which occurs on the hand of the offensive player, while that hand is in contact with the ball, is legal" (NBA rule 12b, section I, paragraph e). In this case, the initial contact took place on Jacksons hand, which was holding the ball.
Analysis: Good no-call. The initial contact to Jacksons hand was legal.
Now regarding the out-of-bounds call....when NBA referees go to the monitor to review plays they have to use a similar burden of proof to what the NFL guys use. There must be irrefutable evidence to overturn the call on the floor. Barnes knocked the ball out of Jackson's hand and the call on the floor was OKC ball. I don't think the refs saw enough evidence in the replay (or the right angle) which would overturn the call on the floor.
Here's the applicable rule:
NBA Rule 8, section II, paragraph c
"The ball is caused to go out-of-bounds by the last player to touch it before it goes out, provided it is out-of-bounds because of touching something other than a player. If the ball is out-of-bounds because of touching a player who is on or outside a boundary, such player caused it to go out. If a player has his hand in contact with the ball and an opponent hits the hand causing the ball to go out-of-bounds, the team whose player had his hand on the ball will retain possession."