We check all of our source code\'s dependent third-party JARs into source control along with our source code. When needed, we manually download updates to third party JARs and r
It's not only about 3rd Party Libraries. Mostly if you have multiple repositories. In our case, we had four repositories with lots of inter- and intra-dependencies. Actually I started this answer and then I had to go for 15 minutes to talk to some colleague about a problem happened after someone forgot to update the .jar of one project in the other's lib directory.
And it looks more professional :)