I was going through the one newly issued patent on "Routing path optimization between sip endpoints". This patent is based on RFC 3261, 3489 etc. I am not sure this is a correct way because IETF contributes for the betterment of the society.
These companies who try to take advantage of open standards and make patents on it looks not ethical for me.
My 2 cents for - if these companies want to build these kind of intellectual property based on open standards, they should publish them as open standards. I don't know the policy of IETF on these issues but its advisable for them to have a policy for the "use of intellectual property" build on top of the open standards so that people who build business using the open standards will not be in trouble.