I know that the ball is oob if it passes over the backboard from either direction. Thought I read somewhere that the ball had to pass "directly" over the backboard. I'm having trouble interpreting what directly means.
Situation 1
In NCAA D-1 final game an Illinois missed fg attempt during the closing minutes appeared to hit the rim and bound over the left corner of the backboard and travel about 2 feet from the left edge of the board.I think the ball even rolled on the top of the board for a while. There was no call. The camera did not follow the ball completely
so it was hard to judge the path of the ball. Let's pretend that it did happen as described. Is this oob?
Situation 2
Similar situation. A1 is 2 inches from the baseline and 10 feet from the rim and shoots the ball over the corner of the backboard. Legal or not?

In this case, the ball hit the top and rolled off the end of the backboard, not over the back of it.

Illegal if the ball passes over the top of the backboard.

There is a video of Larry Bird making this shot that was used in some NBA ad a while back. If you look carefully, you can see the official signalling "no basket."

However, in the NBA if the ball passes over the top of the backboard and does not touch the support or the shot clock, the play is still live. Of of the NBA's rule differences.

In the Illinois-NC game I thought it did roll over the backboard (off the back) not off the end.

It's only illegial if the ball passes over a rectangular backboard right? Meaning that in Situation 2 it would depend on the shape of the backboard? Or not?

NFHS Rule 7-1-2 Note: "When the rectangular backboard is used, the ball is out of bounds if it passes over the backboard."

Yes. For the few HS gyms that still use a fan-shaped backboard, the ball can legally pass over the backboard (so long as it doesn't hit supports, wires etc.).

Z

I thought it was close...so close that the exact angle that the ref saw it from would be critical. It did rebound several feet past the edge of the board.

I don't think so.

<FONT COLOR=BLUE>RULE NO. 8-OUT-OF-BOUNDS AND THROW-IN
Section II-Ball
b. Any ball that rebounds or passes directly behind the backboard, in either direction, from any point is considered out-of-bounds.
</FONT>

So, there you have it. A ball that goes behind the board is OOB...doesn't have to touch anything...doesn't matter how it got there.

That's the NBA rule? Well then I was A) wrong B) misinformed, and C) surprised that this goes uncalled often in the NBA.