Using another company's name in your...

As stated, its best to clear the press release (or any public display of another organization's relationship to you) with the other organization first.  This way they are comfortable with the representation of THEIR company you are broadcasting out to the public.   Take the golden rule... would you want another company broadcasting unknown info about you without your knowledge?

Just ask them.  Most companies and people are happy to allow you to do so becuase they receive free exposure in the market.  If they say no, then you've avoided a potentially much worse situation when they saw the info out there which they did not authorize and decide on legal action or to stop doing business with you.

I know TONS of companies that do.

I would not unless you clear with them first.  If they run a query and see you ranking for their name, there may be problems.