Ask YC: Patent before launching startup?

no one will sue you for patent infringement till you have money, and once you have money, people will sue you whether they have grounds to or not. So I advise fatalism. Don't waste your time worrying about patent infringement. -- http://www.paulgraham.com/softwarepatents.html

We do advise the companies we fund to apply for patents -- http://www.paulgraham.com/softwarepatents.html

A provisional patent, or a patent altogether, puts a stake in the ground to help identify when you invented something.

The actual invention date can be earlier, but a patent is very good proof of the invention date.

Remember this: A patent application must be filed within 1 year of public disclosure of the invention, or you lose the right to patent the invention.

Public disclosure is a pretty low test to meet. Launching your startup will probably pass the test. Disclosing to an employee does not. Disclosing to a contractor may. Be careful here.

Be mindful of the year limit, and keep good notes to prove when you invented something.

If you truly believe the patent would be valuable - e.g. a blocker patent excluding competitors from a valuable opportunity - then it really is worth seeking patent council.

Releasing establishes a prior art date for US patent purposes and starts a 12 month window within which you can file. Releasing your product publicly may mean giving up your rights in certain countries for a global patent filing.

However if your innovation would not be obvious to a user of the product, then releasing may not even constitute disclosure.

Like I said, get some professional patent advice. It probably won't even cost you anything for an initial consultation.

The "one year to file after public exposure" rule only applies to US patents. Publication creates a bar to foreign patents.

If you're planning to rely on the "one year" rule, make sure that you understand what you have to do to use it. At the very least, you need reasonably complete and date-stamped documentation. (No, the "mail it to yourself" scheme doesn't work.) You want to talk to a patent attorney with relevant expertise to find out what's required. You may find that it's easier to simply file a provisional. (A provisional, by definition, is date-stamped.)