Whether it's the Score or just the trumpet part, to COPY and distribute it (sell or give away) without proper permission could easily fall into the category of copyright infringement/violation. Yes, people do it all over the world, every day, but that doesn't make it "OK" from an honesty point of view. I'm not trying to hassle anyone, just wouldn't want anyone to wind up in trouble over illegally distributing copyrighted material.
Cancervivor, if thats true then my band director has been breaking the copyright law all year. He copied the originals, gave them to us, and never asked for them back