Anything?
 

On a throw in after a made basket, A1 throws a pass.

B1 makes contact with the ball after it leaves A1's hand, but the ball has still not crossed the plane from OOB to inbounds.

Is this anything? Tech on B1?

Look up when the restrictions on a throw-in end, and you'll have your answer.

Note: Before Ball Released ...
 

The defender may not break the imaginary plane during a throwin until the ball has been released on a throw-in pass. If the defender breaks the imaginary plane during a throwin before the ball has been released on a throw-in pass, the defender’s team will receive a team warning, or if the team has already been warned for one of the four delay situations, this action would result in a team technical foul.

When did the defender cross the plane of the boundary?

Well, Bob, I have.

I looked at 9-2 and I can't find if the ball has been released by A1 and in the air, but yet to break the boundary line and B2 hits the ball.

I know the rule if the ball is still in possesion of the thrower. Just am unsure if this situation.

Thanks!

Can you describe the throw in a bit more detail? That must a split second action between the thrower's release of the ball and the defender crossing the plane to touch it BEFORE it crossed the inbounds line. Wow!!

Johnny,
As BillyMac and Bob have pointed out, the judgment you must make is WHEN did the hand break the plane? IF the ball was released while the defender was on the inbounds side of the vertical plane, he/she may break said plane to LEGALLY play the ball. On the other hand, IF the ball was still in the inbounder's hands when the defender broke the plane (even without touching the ball), either a warning (if no such warning had previously been given to that team) or a technical (team technical, if the ball was not touched, but a warning had been given and a player technical if the ball was still in the inbounders hands had a warning been previously issued).

Rule 7-6-4 which states:
ART. 4 . . . The opponent(s) of the thrower shall not have any part of his/her person through the inbounds side of the throw-in boundary plane until the ball has been released on a throw-in pass. See 9-2-10 Penalty.

covers this one.

Let me try this, what would you have in this situation?

After a made basket A1 goes to throw the ball inbounds. A1 passes the ball along the endline to A2. A2 has stepped OB to catch the pass (you know the play I am describing here) ...

The ball has been released by A1 and B1 reaches over the boundary of the endline and deflects the pass. The ball is not in possesion of A1 or A2. B1 is standing inbounds.

Does that help?

In this situation it would be a technical foul charged to B1 per Case book play 10.3.10 Situation B.

The key difference is in the Note on 9.2.10. OK to touch on a throw in pass. The pass to an OB teammate is not a throw in pass, therefore the technical.

Johnny,
As I documented earlier, the defense MAY break the defensive plane as soon as the ball has been released for a throw-in (by definition, thrown directly onto the court). However, 7-5-7 states . . . A throw-in anywhere along the end line after a goal or an awarded goal for basket interference or goaltending by a defensive player, as in 9-12 Penalty 1, the team not credited with the score shall make a throw-in from the end of the court where the goal was made and from any point outside the end line.
a. Any player of the team may make a direct throw-in or he/she may pass the ball along the end line to a teammate(s) outside the boundary.

Since this was a pass between A1 and A2, it was NOT a throw-in, therefore, a technical foul is to be assessed (per Case Play already documented).

What if, the ball is in front of A1 and A2? In other words, it's on the inbond side of the end line. Even though both players are out of bounds, is it still a violation since the throw in has not ended?

No violation and the throw-in does end when the ball was legally touched in-bounds as above.

Ignats,
I am not sure exactly whether you are asking a different question completely or if you are asking a question related to the OP. If you are asking a question related to the OP -- in other words, is the defense penalized for touching the ball, in this case, I would ask two questions. If a player holds the ball over the out of bounds line into the court, can the defender touch/grab the ball? In other words, if A1 extends the ball onto the court and B1 grabs the ball resulting in simultaneous possession, do you call a held ball or a technical foul? How YOU answer these questions will lead you to the answer to your question.

As I thought it through after posting------duh. That's what I get for posting before coffee