[TexasAg1996]

There are a couple downsides to a provisional patent application.

Basically, the provisional application is only valid for a year, and it is never examined by the U.S. Patent Office (meaning that it can never become a patent). In order to get a patent, you would need to file a "non-provisional" patent application within a year of filing the provisional application. The non-provisional application could eventually become a patent.

In other words, the provisional application just acts as a placeholder and preserves your rights for a year.

Just a general word of advice - in the U.S., you have a year after you publicly disclose an idea to file a patent application. "Publicly disclose" means you disclose your idea to at least one person without some form of confidentiality in place. If you don't file a patent application within that year, you lose your patent rights. But for most of the world, you lose your rights if you don't file an application before publicly disclosing your invention. So, if you hope to get a patent outside the U.S., make sure to file an application (either provisional or non-provisional) before disclosing your idea. Also, you're right, don't disclose much here.

[ThreePuttinDude]

I got my patent about 3 years ago, and am wondering how long
do patents last before you have to cough up more dough?

[rdb3]

"Publicly disclose" means you disclose your idea to at least one person without some form of confidentiality in place. If you don't file a patent application within that year, you lose your patent rights.

So I should remain silent on the particulars of it until the paperwork is submitted. Will do.