1. If the earlier party is taking legal action against you for infringing the copyrights, you may have to challenge the same on merits in your side.
2. It depends on how strongly you defend your interests.
3. You cannot claim any exemptions to not to prosecute your firm for violating their copyrights.
You may have to defend strongly on the support of documentary evidences in your favor.
Without the opposite party taking any action in this regard you should not indulge into the act of provoking him in the name of taking precautionary or preventive measures.
4. If your copyrights are infringed or violated by a third party you can institute a suit for injunction to restrain them.