3 ms·
For patents, you do need to pay maintenance fees up to the 20 years, however (at 3.5 years, 7.5 years, and 11.5 years, with increasing costs, but they aren't pa
by rcxdude 6y ago
For patents, you do need to pay maintenance fees up to the 20 years, however (at 3.5 years, 7.5 years, and 11.5 years, with increasing costs, but they aren't particularly high)
- dredmorbius 6y agoThanks. I think I may have known that, once.